🛒 Slot bonus buys: is buying the free spins worth it?

How does a bonus buy work?

On slots that offer it, a “Buy” button lets you pay to launch the bonus game, usually free spins, immediately. The price is a multiple of your base stake: at €1 a spin, a 100x buy costs €100. Some studios even offer several buys on the same game, each pricier and more volatile than the last. Examples from our game pages:

• The buy can have its own RTP. The game rules (the “i” button) often list a separate RTP for the buy, sometimes slightly higher than the base game, sometimes slightly lower. Our guide on how to check a slot’s RTP shows where to find it.
• It is not available everywhere. In Great Britain, the Gambling Commission told operators in January 2020 to remove feature buy-ins, which it found did not meet its technical standards. Elsewhere, each casino decides whether to switch it on.
• It does not always combine with other options. On Sweet Bonanza, for example, the buy and the Ante Bet (a 25% higher stake that triggers the bonus more often) cannot be active at the same time.

How much does a buy cost at your stake?

The catch is scale: the stake on screen stays small, but every click is worth 80 to 400 of them. Here is the price of a buy at common stakes.

At €1 a spin, ten 100x buys put €1,000 through the game in ten clicks. Spinning normally, the same amount takes 1,000 spins, roughly an hour of play at a typical pace. The average loss is the same (about €40 at 96% RTP), but it arrives in minutes.

What a buy pays: 8 times out of 10, less than its price

Studios do not publish how their bonus payouts are distributed. To show it, we built a model slot (illustrative, not a real game) set up like many buy-feature slots: 96% RTP, free spins triggering once every 250 spins on average, the bonus making up 40% of the RTP, and a buy priced at 100x the stake. A bonus is worth 96x the stake on average, but that average is pulled up by a handful of huge results.

• 81.9% of buys pay less than their price, and 54.9% pay less than half of it.
• The median result is 30x the stake: on a €100 buy, half the results are €30 or less.
• 8.1% of buys return at least 2x their price, 3.1% at least 5x, 0.9% at least 10x.

Exact figures vary from game to game, but the profile is the same on nearly every buy-feature slot: mostly disappointing bonuses, paid for by a few exceptional ones. That is what high volatility means, as our article on slot volatility explains in detail.

Buy or wait: the cost per bonus

On the same slot, let us compare what it costs, on average, to see one bonus. On a 96% slot, every euro staked costs 4 cents on average, whether it goes into a spin or a buy.

Per bonus, buying is cheaper: you skip paying for the 250 waiting spins, many of which pay nothing. That is the buyers’ argument, and it holds. What it leaves out is what happens on a limited budget, which is every budget.

With €200 or €500: simulated sessions

We simulated 200,000 sessions per case on the model slot at €1 a spin. The player stops after staking €1,000 in total, or when the balance no longer allows play: under €1 when spinning, under €100 when buying (the remainder is kept).

Monte Carlo simulation, 200,000 sessions per column, model slot described above. These are frequencies over a very large number of sessions, not a forecast for yours.

• With €200, buying lowers the chance of finishing ahead (10.8% against 19.8%). Two poor buys are enough to end the session: 87.8% of players can no longer afford a buy before staking €1,000.
• With €500, the chance of finishing ahead is almost the same (25.2% against 25.4%), but the buyer sees more than twice as many bonuses and is twice as likely to land a huge one. The price: half the sessions stop because another buy is unaffordable, and the median balance drops to €100 against €301.
• The average loss does not change: it depends only on the amount staked and the RTP. Buying pushes results towards the extremes.

Rule of thumb from these numbers: if your budget does not cover at least five buys, buying mostly means playing your whole balance in two or three shots.

With a welcome bonus active, buying is almost always off the table

A buy is charged in one go, so for the casino it is a single bet of 80 to 400 times your base stake. While a bonus is active, the terms set a maximum bet per spin. The maths is quick:

To stay under a €5 maximum bet, you would have to buy at a €0.05 base stake, while most popular slots start at €0.20 (as Sweet Bonanza does). A buy under a bonus therefore breaks the limit, and breaking the maximum bet is one of the most common reasons for winnings being voided. Some terms go further and exclude buys from wagering, or ban them outright.

Bottom line: if you plan to buy bonuses, play without a welcome bonus, or finish the wagering first. Our bonus calculator shows how much you need to stake before you are free.

Where to find slots with a bonus buy

Hacksaw Gaming and Nolimit City are the studios that put buys on most of their recent games, often several per game. According to our reviews, 14 casinos in our selection carry them, 7 of them both:

List built from the providers recorded in our reviews; a paused casino drops out automatically. A studio being in the lobby does not guarantee the buy is enabled: it depends on the casino and your country, so check in the game.