Best RTP Casino Slots UK: Understanding Returns
RTP describes a slot’s long-run relationship between stakes and returns, while volatility shapes how those returns may be distributed.
What an RTP Figure Can—and Cannot—Tell You
RTP stands for return to player. An advertised RTP figure describes the mathematical return built into a slot over a sufficiently large number of plays. It is not a record of what you will receive from the next spin, the current session, or even a short run of sessions.
Think of the figure as a property of the game’s design. The game determines how often winning combinations can occur, how much they pay, and how those payments are distributed across all possible outcomes. RTP summarises the resulting long-run relationship between money staked and money returned. It does not identify the result of any particular sequence.
That distinction matters because random outcomes do not arrive in a smooth order. A slot can produce several wins close together, followed by a long period with fewer successful combinations. It can also do the reverse. The advertised return remains the same design measure in both situations, but the player’s actual balance can move very differently.
Long-run average, not an individual result
Suppose a game’s RTP is described as a proportion of the stake returned over the long run. That wording has two important parts.
First, it refers to an average across a large body of play, not to each individual bet. A single spin either produces a particular outcome or does not; it cannot deliver the long-run average in a literal, balanced form.
Second, the average applies to the game’s complete mathematical model. It includes losing outcomes, ordinary wins, larger wins, and any other outcomes included in the game rules. A player may encounter only a small part of that model during one visit.
This is why an outcome above the advertised return does not prove that the game is “due” to pay less next. Nor does a poor session prove that a balancing win must arrive. Previous spins do not create an obligation for later spins. Treating the RTP as a running account that the slot must settle during your session confuses a statistical property with a promise.
The same principle applies when comparing high-RTP online slots. A higher stated return can indicate a smaller built-in disadvantage in the mathematical model, but it cannot tell you which game will produce the better result during a particular visit. The figure describes expectation across extensive play; it does not rank the luck of individual sessions.
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The house edge is the other side of the calculation
A slot with a positive house edge is designed so that the mathematical expectation for the player is negative over enough sessions. In plain terms, the game’s long-run average return is below the amount staked. The difference is the casino’s mathematical advantage.
This remains true whether losses appear gradually or arrive in noticeable drops. A player might experience a long sequence of small changes, an early large win, or an uneven mixture of outcomes. None of those patterns removes the underlying advantage. The pace and shape of the results can change how the experience feels, but not the expectation built into the game.
A positive house edge also does not mean that every session must end in a loss. Random play can produce profitable sessions, sometimes by a considerable margin. It can also produce losses even when a player chooses a game with a relatively favourable advertised return. The house edge describes the direction of the average over enough sessions, not the sign of every individual balance.
What the figure is useful for
RTP is useful when you want to understand the structural cost of a slot and compare the mathematical design of games on a consistent basis. It gives you a way to distinguish the game’s theoretical return from claims based only on attractive themes, recent outcomes, or an isolated winning story.
It is also useful for separating two decisions that are often mixed together. The RTP figure concerns the game’s long-run return model. Your session result depends on the outcomes generated during your play. The first can be studied from the game information; the second cannot be known in advance from the advertised figure.
Read the figure as an estimate of the game’s long-term behaviour, not as a target the slot must reach while you are playing. It does not predict the next spin, recover a previous loss, or turn a negative-expectation game into a favourable investment. Once a positive house edge is present, the mathematical expectation remains negative over enough sessions, regardless of how slowly or quickly the losses become visible.
RTP summarises the resulting long-run relationship between money staked and money returned. It does not identify the result of any particular sequence.
How RTP Applies to a Slot Bet
RTP belongs to the game’s mathematical model, but the model operates through the bets you place. To interpret a return figure correctly, first identify what the game treats as one complete bet: the stake, the selected lines or ways to win, and any features included in that game mode. The advertised RTP describes the theoretical return associated with that betting configuration over a sufficiently large number of plays. It is not a separate payment added to each spin.
A slot can show several betting choices while remaining one game. You might be able to change the stake, select a different number of paylines, or adjust the value assigned to each line. Those controls alter how money is committed to a spin. They do not turn RTP into a cash balance that is distributed after every result. The relevant question is always: what exactly has been wagered, and which outcomes can that wager activate?
The stake is the unit being tested
Suppose you place a bet and the reels stop. The result is determined for that game cycle, and any winning combination is settled according to the game’s paytable. RTP does not calculate the result by taking your individual stake and returning a fixed portion of it. A losing spin can return nothing, while another spin can pay a prize larger than the stake. The return figure describes the relationship between total stakes and total payouts across the game’s mathematical operation, not the result of one isolated bet.
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This distinction matters when you compare different stake settings. If the game’s rules keep the same betting arrangement and you increase the value of the stake, the monetary size of both wins and losses changes. The underlying return rate is not a prediction that the higher bet will produce a proportionally better session. It means that the same mathematical design is being applied to a different amount of money per game cycle.
A change in the arrangement can be more significant than a change in the stake. If selecting or removing lines changes which combinations are active, you are no longer looking at exactly the same wager. The paytable may also define different awards for different patterns, so you must read the game’s information panel rather than assume that every displayed RTP label applies to every available setting.
Reels and paylines are separate parts of the mechanism
The reels are the columns that display the symbols. Paylines, ways to win, or other approved patterns determine how symbols are evaluated after the reels stop. These are related, but they are not interchangeable terms. A game may display several reels while using a different method to decide whether a result wins.
A five-reel slot can use one bet that covers all five reels. In that arrangement, the wager is not five unrelated bets simply because five columns are visible. The game evaluates the completed reel result according to its rules, and the stake is applied to the relevant combinations across the reel set. This is why counting reels alone cannot tell you what a spin costs or what the RTP figure describes.
Do
- Open the paytable and betting information before placing a bet.
- Check which reels are involved and how symbols must appear.
- Identify the cost of one game cycle and what the bet activates.
Don’t
- Assume every displayed RTP label applies to every available setting.
- Treat the RTP as a running account that the slot must settle during your session.
- Confuse the RTP figure with a prediction of your next spin.
The number of reels also does not tell you how many winning patterns are active. A five-reel game may use paylines, symbol clusters, ways to win, or another evaluation system. Before placing a bet, open the paytable and betting information. Check which reels are involved, how symbols must appear, whether the order matters, and whether the selected stake activates the available patterns.
Read the paytable beside the RTP information
RTP is easier to interpret when you read it alongside the game’s rules. The paytable explains the conditions for a win; the betting panel explains the amount committed; the RTP information describes the model’s long-run return for that setup. None of these elements can replace the others.
Paytable symbols may have different values depending on where they appear or how many matching symbols are required. Some games may include special symbols, bonus features, or alternative win systems. If those features are part of the game’s designed outcomes, their payouts are included in the mathematical model represented by the RTP figure. You should therefore avoid treating the figure as though it applies only to the ordinary reel symbols shown during a basic spin.
The wording attached to a game can also distinguish between a default setting and selectable options. If the interface offers several modes, inspect the information for the particular mode you intend to use. A headline RTP figure without its betting context is incomplete information: it tells you a property of a model, but not necessarily which button settings produce that model.
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Do not confuse stake size with coverage
Applying a bet across all five reels does not mean that you are guaranteed to receive a return from each reel, nor does it mean that every visible symbol creates a separate payment. Coverage describes how the game processes the wager. The outcome still depends on the symbols, the winning rules, and the paytable.
Likewise, increasing the stake does not buy a more favourable result on an individual spin. It increases the amount exposed to the game’s rules. If a win occurs, the prize may be calculated from the stake or from the value assigned to the relevant line or combination, depending on the game. The information panel should show how that calculation works.
When assessing RTP slots, begin with this mechanical check: identify the cost of one game cycle, determine what the bet activates across the reels, and confirm which payout rules are included. Only then does the advertised return figure have a clear meaning. It describes the designed relationship between wagers and payouts for that betting structure; it does not describe a fixed return attached to every spin.
Why the Highest Advertised RTP Is Not a Session Forecast
A slot carrying the highest advertised RTP is not necessarily the one that will return the most during your next session. The figure describes a mathematical property of the game under its stated configuration; it does not describe the result that will appear on your screen after you play.
That distinction matters because a ranking turns one abstract measurement into a practical recommendation. If you sort games from the largest advertised RTP to the smallest, you have created an order based on expected long-run performance. You have not created an order of likely short-term outcomes. The first game on that list can produce a losing session, while a game lower down can produce a profitable one.
Attention A higher stated return can indicate a smaller built-in disadvantage, but it cannot tell you which game will produce the better result during a particular visit.
What the headline figure actually ranks
The advertised RTP is useful for comparing the theoretical return associated with different slot configurations. All other relevant conditions being understood, a higher figure indicates a smaller mathematical disadvantage for the player over sufficiently extensive play. That makes it a meaningful comparison point when you are examining slots with the highest RTP.
It does not, however, measure the quality of a particular session. A session consists of a limited sequence of outcomes, and those outcomes are not required to resemble the long-run proportion represented by the headline. The calculation does not reserve part of the stated return for you, nor does it create a balance that a game must correct after an unlucky run.
This is why “best RTP” and “best result today” are different descriptions. The first concerns the structure of the game. The second concerns an outcome that has not yet happened and cannot be established by the advertised figure alone.
Why a higher ranking cannot guarantee a result
A slot outcome is generated for each completed game cycle. The advertised RTP is not a schedule showing when wins will arrive or how they will be distributed between sessions. It does not tell you whether your next sequence will contain a winning combination, how large that combination will be, or whether several outcomes will occur without a return.
Consequently, the highest-RTP online slots cannot be treated as a set of reliable short-session choices. A high position in a comparison does not remove the uncertainty of individual outcomes. It only indicates that the game has a particular theoretical return relative to games with lower stated figures, assuming the figures refer to comparable versions and conditions.
The same limitation applies when a title is described as one of the highest RTP casino slots in the United Kingdom. Adding a location or a current year to the description does not convert a theoretical measure into a forecast. The game still produces individual outcomes, and the headline still cannot specify what your own play will yield.
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The house edge remains part of the comparison
RTP is often read as though it were a promise of money coming back. For decision-making, it is more accurate to view it as the other side of the house edge. Where the casino retains a positive mathematical edge, the player’s expected result is negative when play is considered across enough sessions. The speed at which that disadvantage becomes visible can differ, but changing the pace does not reverse the underlying expectation.
This has an important consequence for lists of the best RTP online slots. A list can identify games with a more favourable theoretical return than other games, but it cannot identify a slot that removes the casino advantage. Even the top entry remains a gambling product with an unfavourable expectation for the player over sufficiently extensive play.
Short-term results can therefore sit far from the ranking suggested by the advertised figures. A player may finish ahead on a game with a less favourable theoretical return, while another player may lose on a game presented as having the most favourable one. Neither result disproves the figure, because neither is a measurement of the long-run property it represents.
How to use a high-RTP comparison sensibly
Treat the figure as one filter rather than a prediction tool. It can help you distinguish the stated mathematical terms of one game from those of another, but it cannot tell you which title will win in a particular session or determine whether a session will end in profit.
Avoid reading labels such as “highest RTP slots UK” or “best online slots RTP” as if they meant “most likely to pay you now”. They do not establish a ranking of immediate outcomes. They describe a comparison of advertised theoretical returns, and that comparison has limits even when the figures are presented with confidence.
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A careful reading keeps two questions separate: which slot has the more favourable stated mathematics, and what will happen during your play? The first may be addressed by comparing the advertised RTP. The second remains unknown before the relevant game cycles occur.
Playing High-RTP Slots at a UK-Licensed Casino
Finding a slot with a high advertised RTP and choosing a suitable casino are separate tasks. The game’s listing tells you about the game, while the operator’s licence tells you whether the business is authorised to offer gambling to customers in Great Britain. Check both before depositing.
The relevant regulator is the UK Gambling Commission. It oversees commercial gambling in Great Britain, including remote gambling, and its authority does not depend on where the operator’s servers or other key equipment are located. A casino serving Great Britain therefore needs the appropriate Gambling Commission operating licence even if the company itself is based elsewhere. The Commission also issues personal licences to individuals who perform specified operational roles.
Check the operator before the game
Do not treat a game catalogue, a familiar brand, or a polished website as evidence of authorisation. Use the UK Gambling Commission’s public register to confirm that the operator has a current operating licence. Check the licence number shown by the casino against the register rather than relying only on a logo or a claim in promotional material.
This check answers a different question from “where can you find a high-RTP slot?” A provider may distribute games to many operators, but each casino remains responsible for its own permission to offer real-money gambling. The same title can therefore appear in different casino catalogues without making those operators equivalent choices.
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A licensed operator also has to meet the requirements that accompany its permission to operate. These include verifying your age before allowing you to deposit, providing account-level financial-limit controls, and offering responsible-gambling tools such as self-exclusion. UK Gambling Commission licensees must also provide an internal complaints route and access to an approved Alternative Dispute Resolution service. Those features concern the operator, not the slot’s advertised return.
Confirm the slot stake limit
Before you deposit, check that the casino’s terms and the game interface apply the correct stake limit to your account. A specialist review reports that the maximum stake for an online slot game cycle is £5 for customers aged 25 and over, while customers aged 18 to 24 are limited to £2. Treat the review as a pointer, then verify the current position through the licensed operator and the regulator’s information, because regulatory conditions can change.
The limit applies to the total amount staked in one online slot game cycle. It is not a recommendation about how much to play, and it does not identify a high-RTP game. If the stake selector, paytable, or casino terms appear inconsistent with the applicable limit, do not deposit until the operator explains the discrepancy.
This also helps separate slot rules from general casino rules. The limits discussed here concern online slots; they should not be assumed to describe every casino game. A casino may offer slots, roulette, blackjack, and other products under the same account, but the relevant conditions can differ by product.
A practical order of checks
Use this sequence when comparing places to play:
- Confirm the casino’s current UK Gambling Commission operating licence on the public register.
- Check that age verification is required before depositing.
- Read the slot terms and confirm the stake limit for your age group.
- Check that the game is available for real-money play at that operator, rather than only as a demonstration.
- Review the available financial-limit, self-exclusion, complaint, and Alternative Dispute Resolution information.
Only after these checks does it make sense to compare the games in the casino’s lobby. The licence establishes whether the operator may serve you; it does not turn a particular RTP figure into a promise about your results.
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Evaluating RTP Claims for Individual Slot Games
An RTP claim attached to a named slot should be treated as a specification to verify, not as a reason to place the game at the top of a ranking. The useful question is not simply whether a page describes a title as “high RTP”. It is whether the stated figure clearly belongs to that particular game and to the version you can actually play.
Start with the game’s own information panel or rules. Look for the return figure alongside the title, provider and relevant game details. A claim is easier to assess when these elements identify one precise product rather than a general group of games. A page that mentions several titles but gives no game-specific figure does not establish which one has the greater return.
The wording also matters. “High RTP” is a description, not a measurement. “Best” is a ranking claim, so it requires a consistent basis for comparing the titles included. If one page uses a precise return figure for one game and broad promotional language for another, the two descriptions cannot support a reliable order. A list of the highest-return games should therefore show a comparable, traceable figure for every entry.
Check whether the claim comes from an identifiable gambling operator, the game provider, or the slot’s rules. Marketing copy can draw attention to a favourable characteristic without explaining the conditions attached to it. The rules or information screen should make clear that the figure concerns the slot’s theoretical return, rather than a promise about a particular player’s results.
Volatility
Volatility describes how a slot’s results are distributed over time. It determines whether a game produces frequent small wins or infrequent larger wins.
The provider is another useful identity check. Similar names, themed editions and games offered in several places can make it unclear which title a description refers to. Record the exact game name and compare it with the title displayed in the casino interface. If the provider is shown, use that detail to distinguish the product from similarly branded entries.
Do not treat a game’s availability on a UK-facing website as proof of a particular RTP. Availability tells you where the title can be accessed; it does not, by itself, verify the numerical claim. Equally, a casino label such as “featured” or “popular” says nothing about mathematical return.
A careful comparison can use a simple checklist:
- Is the exact game name stated?
- Is the RTP figure attached directly to that game?
- Is the provider identified?
- Can the figure be found in the game information or rules?
- Are all compared titles described using the same kind of evidence?
- Does the wording distinguish a theoretical return from an individual outcome?
If any answer is unclear, describe the title without ranking it. That is more accurate than presenting an attractive but unsupported list of the best RTP slot games. A named game may still interest you, but its advertised return should remain a documented characteristic to check, not evidence that it will outperform another title during your session.
What a 98% RTP Claim Does Not Mean
A 98% RTP claim describes a theoretical return rate calculated across a sufficiently large number of plays. It does not state what you will receive from one spin, one bonus feature, or one gambling session. The result in front of you can be far above or below the advertised figure because the calculation is not a short-term forecast.
The word “claim” matters. A displayed RTP is a property assigned to the game’s mathematical model, not a payment owed to an individual player. It does not set a minimum return for your session, and it does not make a particular outcome more likely merely because the stated percentage is high. Two sessions on the same game can produce very different balances while remaining consistent with the same underlying model.
The threshold also does not identify the way returns will arrive. A 98% figure says nothing by itself about whether wins are frequent, whether they are concentrated in particular features, or how widely individual results can vary. Those are separate characteristics. A game may present a high stated return while still giving you an unsuccessful session.
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Most importantly, 98% is not the same as a fair game. RTP below 100% represents a mathematical advantage for the game over the long run. In other words, the percentage does not remove the house edge; it describes the size of the expected disadvantage built into the game. The effect may be barely noticeable during a short period, or it may appear through a sequence of losing results, but changing the pace at which losses emerge does not change the underlying expectation.
This is why a search for slots with RTP of 98% or higher should be treated as a request for a mathematical characteristic, not as a promise of a profitable session. Adding a preference for low volatility or low variance does not alter the meaning of the 98% threshold. It may describe a different pattern of outcomes, but it cannot turn the stated return into a personal forecast.
A high figure can therefore be relevant when comparing the mathematical design of games, provided the figure is understood correctly. It cannot tell you how much a particular deposit will return, whether a session will finish in profit, or when the stated long-run behaviour will become visible in your own play.
How Volatility Changes the Shape of Returns
Volatility describes how a slot’s results are distributed over time. It does not describe the total return figure by itself. Two games can advertise the same long-run return while producing very different sequences of wins and losses because their prize patterns are arranged differently.
Volatility Patterns
Low Volatility
Typically produces more frequent, smaller wins, often occurring every three to six spins on average.
High Volatility
Results tend to occur less often, with larger winning amounts when they do arrive.
A low-volatility slot generally spreads its winning outcomes across more spins. The individual wins are often smaller, but they occur more frequently. Across most titles, low-volatility games typically produce a winning combination every three to six spins on average. That is a description of the usual distribution, not a schedule: a particular run can contain several losing spins in succession, followed by more than one win close together.
A high-volatility slot uses a different distribution. Winning combinations tend to occur less often, while the successful outcomes are larger when they arrive. This creates longer gaps between noticeable wins and makes the balance move more sharply in either direction. A player may therefore experience a quiet sequence followed by a substantial payout, rather than a steady series of modest returns.
The difference can be represented simply:
| Volatility | Typical outcome pattern |
|---|---|
| Low | More frequent, smaller wins |
| High | Less frequent, larger wins |
This table describes the shape of results, not whether a game is mathematically favourable. Volatility does not turn a negative-expectation game into a positive one, and it does not establish how much a particular session will return. It only helps explain how the results may be spaced and sized.
When comparing casino slot RTP and volatility, treat them as separate properties. RTP is a long-run return measure; volatility concerns the path by which outcomes are distributed. A game with a high advertised RTP can still feel uneven if its volatility is high. Conversely, a lower-volatility game can produce regular small wins without changing the underlying mathematical expectation.
For that reason, choosing between low- and high-volatility slots is primarily a decision about the pattern you are prepared to experience. Low volatility may make the balance change in smaller steps, whereas high volatility may produce fewer but more pronounced movements. Neither label predicts the result of the next spin.
High-RTP Slots Played for Real Money
A high RTP can make a slot’s mathematical disadvantage smaller, but it cannot remove that disadvantage when the game still has a positive house edge. RTP describes the return built into the game over a sufficiently large number of bets. It does not turn each real-money spin into a fair exchange, and it does not determine what will happen during your particular playing session.
That distinction matters because real money makes each outcome concrete. A losing spin reduces your balance, while a winning spin adds to it according to the game’s rules. The RTP figure does not reserve a corresponding return for your account, repay losses after an unlucky sequence or identify when a favourable result should appear. Nothing in the figure changes the random result of the next spin.
The relevant calculation is an expectation, not a promise. If the game retains a positive mathematical edge, the expected result for the player remains negative when play is considered across enough sessions. The losses may arrive in a pattern that feels gentle, with wins appearing between them, or in a sharper sequence. Their pace and visibility can change, but the underlying disadvantage does not.
Does a high RTP guarantee a profit?
No. RTP is a mathematical property of the game’s design over extensive play; it does not predict the outcome of any specific session.
What is the difference between RTP and volatility?
RTP is a long-run return measure, whereas volatility concerns the path and distribution by which those outcomes are delivered.
How much can I bet on a UK slot?
For customers aged 25 and over, the maximum stake is typically £5 per cycle, while those aged 18 to 24 are limited to £2.
This also applies to slots advertised with a very high return figure. Such a claim may be useful when comparing the mathematical structure of games, yet it cannot establish that a real-money session will finish ahead. A short session can produce a profit, a loss or a balance close to the starting point without contradicting the advertised RTP.
Treat the figure as one property of the game rather than as a forecast for your funds. Decide in advance what amount you can afford to lose, keep that amount separate from essential spending and stop when it is gone. A high-RTP slot can reduce the built-in disadvantage relative to a lower-RTP alternative, but it remains a game played against a positive house edge.
Low Volatility and RTP Above 97%
A slot can be described as both low volatility and having an advertised RTP above 97%, but these labels refer to different properties.
RTP is a return calculation attached to the game’s mathematical model. It describes the proportion of stakes the model is designed to return over a sufficiently large number of plays. A threshold such as 97% or 98% therefore concerns the game’s long-run return figure, not the size or regularity of wins during your session.
Volatility describes how that return is distributed. Low-volatility slots tend to spread returns across many smaller wins. High-volatility slots tend to produce winning outcomes less often, with larger amounts when they occur. A low-volatility game can therefore feel more active because winning combinations appear more regularly, while the individual wins may be modest.
These characteristics can exist together, but neither one proves the other. A low-volatility design does not automatically have RTP above 97%. Equally, an advertised RTP above that threshold does not show that the slot is low volatility. You need to assess the two descriptions separately.
The combination may suit you if you prefer a steadier pattern of smaller winning outcomes and are also looking for a stated return figure above the chosen threshold. However, the volatility label cannot turn the RTP figure into a session expectation. Frequent small wins may still leave the balance lower, and a high stated RTP does not guarantee that the preferred pattern will appear in a short run.
When comparing a game described in these terms, treat the RTP and volatility statements as separate technical information. Confirm that both refer to the same version of the slot and the same configuration. Then consider whether the distribution of wins matches your tolerance for changing balances. Low volatility concerns the shape of outcomes; RTP above 97% concerns the model’s stated long-run return. Neither is a forecast of what your next spins will produce.
Can a Slot Really Have 99% RTP?
A slot can be described with a 99% RTP figure, but that label must be understood as a mathematical return rate, not as a forecast for your next spin or session. It describes how the game is designed to perform across a sufficiently large volume of play. It does not assign a fixed share of each stake back to every player.
The distinction matters because slot results are produced in individual game cycles. A session can contain several wins, no meaningful win, or a result that differs substantially from the advertised long-run rate. The RTP figure does not determine the order of outcomes, the size of each win, or the point at which a session ends. A high stated return therefore cannot tell you what your balance will be after playing.
The number also does not remove the house edge. If the game retains a positive edge, its mathematical expectation remains negative over enough sessions, even when losses appear gradually and the stated RTP is very high. The percentage changes the size of that disadvantage in the model; it does not turn the game into a positive-expectation activity.
That is why the question “what slots have 99% RTP?” has two separate parts. One concerns whether a particular game is presented with that numerical specification. The other concerns what you may receive while playing it. The first is a description of the game’s theoretical return. The second is an uncertain session outcome, and the first cannot be used as a promise about the second.