Naming the best online slots sign up bonus or welcome offer is a subjective task. Different aspects of slots new customer offers matter to different players.

Are you looking for the highest matched deposit bonus or the lowest wagering requirements, the best no deposit online slots bonus or the most free spins?

This Telegraph betting guide introduces you to the best online slots offers and bonuses in each of those categories and more. Scroll down for the best slots bonus offers.

Best online slots sign up bonus for matched deposit: bet365 Slots

 The online slots sign up bonus you see more often than any other is the matched deposit bonus, so readers can be assured bet365 beat off some intense competition in this category.

 New slots players can take advantage of similar offers at 32Red, Betfair and William Hill, but the bet365 slots bonus for new players stands out due to its low wagering requirements.

Bonus wagering requirements are substantially lower than many of the other bookies and casinos promoting similar new customer slots bonuses. Up to three times in most cases.

Other UK online slots providers may match your deposit up to a higher amount, or even give players a bonus of more than 100% of their first deposit, but bet365’s lower wagering puts far less play-throughs between players and real money winnings from their bonus funds.

Best online slots no deposit sign up bonus: 888casino Slots

Still sought after but less commonly found than was once the case, the no deposit bonus still has a champion in one of the oldest surviving online casinos, 888casino.

Pieces of eight have long been associated with treasure and no-deposit-bonus-loving slots players have every reason to treasure this offer from 888casino. £88 to play with and no deposit required.

Alongside this notable upside, is another. Where most online slots UK operators’ bonuses expire after seven days 888 double your timeframe, giving players 14 days to play through their bonus before it expires.

Best online slots sign up bonus for free spins: William Hill Slots

What could be better than a welcome offer featuring a generous helping of free spins to help you try out the games on offer at an online slots site?

That’s right, a bonus offer that combines free spins with a 100% bonus on your first deposit up to an exceptional £300.

Best online slots sign up bonus for low wagering requirements: Grosvenor Slots

Experienced online slots bonus aficionados will now any slots sign up offer is only as good as the wagering requirements attached. Grosvenor’s online casino has the lowest around.

If you read why the bet365 slots sign up offer was so good above you’ll know just how much lower the 5x wagering requirements on the Grosvenor slots bonus is than many of their rivals.

A matched deposit offer up to a maximum of £20 may seem small beans compared to some online slots providers’ sign up bonuses. Yet, you can withdraw any winnings after playing through your bonus five times instead of 45 or more. Do the math.

 Best online slots sign up bonus for first-deposit-to-bonus ratio: Paddy Power Slots

Matched deposit bonuses are brilliant if you want to deposit a large amount into your new account. However, if you want to land a healthy sign up bonus in return for only a small outlay then the Paddy Power slots bonus is the one for you.

 This type of slots bonus for new customers is ideal for slots rookies, or simply for players that want to experience plenty of play at a new slots provider without staking loads.

BetVictor and Unibet have similar offers to Paddy Power and some operators even give you more bonus funds in return for £10.

Two things make the offer from the Irish slots firm stand out. The first is a relatively moderate 35x wagering requirement on the bonus and any winnings that arise from it. Second is the bonus’ seven-day expiry time – more than double that of similar bonuses from other bookies.

Best online slots sign up bonus honourable mentions

The online slots sign up offers below may not have been selected for one the awards above, but all came very close to doing so in at least one of the categories.

As a result these sites are well worth taking a look, not least because taking advantage of new customer offers is part of the fun when it comes to online slots sites. 

32Red Slots

Unlucky not to claim outright victory in the ‘best online slots sign up bonus for matched deposit’ category, this 32Red slots bonus offer for new customers provides a massive 150% matched deposit bonus up to a maximum of £150.

It’s fair to say that 150% is one of the biggest slots deposit bonuses around, making this one of the go to new customers offers for slots players who want to be rewarded for making a substantial first deposit.

Betfair Slots

Yes the firm is known first for its exchange and more recently its sportsbook is also home to an excellent online slots selection.

New customers can claim a 100% deposit bonus up to a maximum of £100 to sample Betfair slots in all its glory.

BGO Slots

The BGO slots bonus for new customers will appeal to free spins seekers that relish the potential for a mammoth haul of gratis goes in return for their £10 first deposit.

Your first deposit bonus equates to spins on their Mega Wheel where you can win up to 500 free spins worth 50p a spin.

Betfred Slots

The Betfred slots sign up offer is the kind of bonus that’s ideal for online slots rookies.

It combines a low required opening deposit of £10, with a handy 50 free spins to see if the site is for you. There are also no wagering requirements on any winnings you get from the free spins.

BetVictor Slots

Another quality sign up bonus that gives you a big bonus for a relatively small first deposit.

Bear in mind you have to wager the first £10 on Casino Games with your first deposit. This offer is designed to introduce you to all aspects of the Casino. As such your bonus includes £20 for slots play alongside other bonus amounts for other aspects of the site.

Unibet Slots

The Unibet slots sign up offer is a generous bonus that gives new players a chunky £40 to play their online slots but it stands out from other new customer offers for another reason.

That reason? Most online slots bonuses for new players expire after seven days. New customers at Unibet have an unhurried 30 days to play with their bonus funds.

Want all the best online slots bonuses and sign up offers in one place?

The Telegraph Betting Slots Offers page is always being updated with the latest new customer welcome bonuses.