How We Review Slots

Every slot review on UnionSlots answers three questions: what the game is, whether it is worth your time, and where you can play it legally in the UK. This page explains how we check the facts, how we arrive at our rating out of 10, and what we will not do.

What we review

We review online slots that are offered at casinos licensed by the UK Gambling Commission (UKGC), plus the UKGC-licensed casinos and payment methods UK players use to play them. We do not review or link to casinos that are not licensed in Great Britain, including sites that operate outside GamStop.

How we check the facts

Each review starts with a facts table: provider, release date, RTP, volatility, reels and paylines (or ways to win), minimum stake, maximum win and the main features. Numbers such as RTP, maximum win, provider and stakes are taken from the provider’s own game page, or confirmed by at least two independent databases when the provider does not publish them.

  • When sources disagree and we cannot resolve it, we say so or leave the figure out. We would rather show no maximum win than a wrong one.
  • Many slots come in several RTP versions. We quote the standard version and remind you to check the game’s information screen at your casino.
  • We describe how the features actually trigger and pay, in plain English, rather than copying the provider’s marketing.

How we rate slots

Our rating is an editorial score out of 10, in half points. It reflects four things:

  1. Return and risk. RTP compared with the 96% that is common today, and how clearly the volatility matches what the game offers.
  2. Features and gameplay. How much the bonus rounds add, how they are triggered and whether the base game holds up between them.
  3. Transparency. Whether the rules, the maximum win and the RTP versions are published clearly.
  4. Fit for UK players. Availability at UKGC-licensed casinos, the stake range under the UK limits and how the game plays on mobile.

As a guide, 8 and above is a standout game, 6.5 to 7.5 is a solid game with clear catches, and below 6 is hard to recommend. Every review lists the pros and cons behind the score.

How we review casinos

Before a casino appears on UnionSlots we check its licence on the UKGC public register. Our casino reviews then look at the welcome offer and its key terms, deposits and withdrawals, the slot library, safer gambling tools and customer support, and we state anything we could not confirm.

UK rules we apply in every review

  • Online slot stakes are capped at £5 per spin, or £2 if you are aged 18 to 24.
  • Autoplay and turbo spin features are switched off, and bonus buy features are not available in Great Britain.
  • Bonus wagering requirements are capped at 10 times the bonus.
  • Credit cards cannot be used for gambling.
  • Age and identity checks are required before you can play, including in demo mode.

What we do not do

  • We do not host demo games. UKGC-licensed casinos offer demo mode after registration and age verification.
  • Casinos and game providers cannot pay for a better rating, and they do not see or approve our reviews before publication.
  • We do not promise wins or suggest that any strategy beats the house edge.

We earn money from some of the casinos we list. How this works, and how we keep it separate from our ratings, is explained in our affiliate disclosure.

Keeping reviews accurate

We correct a review as soon as we find an error or a provider changes a game, and we re-check our facts when we update a page. If you spot something wrong, please tell us through our contact page.

Gambling responsibly

Slots should stay a paid-for form of entertainment. Set a budget before you play. If gambling stops being fun, call the National Gambling Helpline free on 0808 8020 133 (24/7, run by GamCare) or self-exclude from all UKGC-licensed sites with GamStop. More help is on our responsible gambling page.