21LuckyBet US Open Cashback: Get 10% Back up to £500

21LuckyBet is running a limited-time cashback promotion for tennis bettors during the opening days of the 2026 US Open. Players who join the offer can recover 10% of qualifying losses, with the cashback capped at £500.

The tournament itself runs into September, but this cashback deal is only active between 23 and 26 August 2026, so the qualifying window is much shorter than the full event.

How to qualify for the 21LuckyBet cashback

To enter the promotion, make a deposit of at least £10 through the sports cashier and apply the promo code USA10.

Once the deposit has been made, place real-money wagers on tennis. Only qualifying losses generated during the promotional period are used to calculate the cashback.

If eligible, 21LuckyBet returns 10% of those losses, up to the maximum promotional limit of £500.

What bets are eligible?

The promotion applies exclusively to single tennis bets placed with real money. Bets must also be fully settled before they can count towards the cashback calculation.

Accumulators, multiples and chain bets are excluded from the offer.

Any cashback earned is issued with a 0x wagering requirement, meaning there is no additional turnover requirement attached to the reward. It is credited to the player’s real-money balance within 7 days and can then be withdrawn or used for standard betting.

Terms and conditions of the promotion

The 21LuckyBet US Open Cashback offer runs from 00:00 GMT on 23 August 2026 until 23:59 GMT on 26 August 2026.

Participation requires a minimum £10 deposit, the use of promotional code USA10, and a deposit made specifically through the sports betting cashier. Customers must also be 18 or over and eligible to receive promotional bonuses.

Cashback is based on qualifying deposit losses from settled single tennis bets during the offer period and is limited to £500. Bonus amounts are rounded down to two decimal places.

Payments made via Skrill or Neteller are not eligible. In addition, submitting a withdrawal request can cancel active or pending bonuses where the relevant promotional requirements have not yet been satisfied.