[sufue]

Well, the $5 on $20 credit deal in the US must have been successful, because it's being replicated at Kindle UK. This time it's £3 on £10, has to be activated, and as in the US, you get to count books you bought during the entire offer period, June 5 to June 11, even if you hadn't yet activated the offer when purchased.

This appeared as a banner at the top of my page while browsing at Kindle UK, and when I clicked through, I came to this webpage: https://www.amazon.co.uk/b?node=21579382031

But I'm not sure how helpful that link will be since they seem to imply it's a targeted offer...so YMMV.

Lots of other finicky rules, and here they are:

FAQ

Spoiler:

Frequently Asked Questions:
How do I get my Kindle Book credit?
Customers receive their Kindle Book credit after activating the offer and spending £10 or more on any one or more Kindle Books between June 5 and June 11, 2020 (in one or multiple transactions). You must activate your offer by clicking “Get offer” any time during the offer period in order for your purchases to count.

What if I haven't activated the offer?
If you have landed on this page without clicking on the offer email or offer push notification sent by us directly to you or without clicking on the offer banner on Amazon.co.uk, please click here - Get offer, wait for this page to reload and start shopping for Kindle Books

Which Kindle Books count towards the offer?
Any Kindle Book that you purchase on Amazon.co.uk during the offer period will count, including Kindle Book gift orders, bulk Kindle Book orders, and pre-orders that are fulfilled during the offer period. Activation can occur at any time during the offer period. Pre-orders that are fulfilled outside of the offer period are excluded from this offer.

When is the offer period?
The offer period is between June 5 and June 11, 2020.

When do I get my credit?
Your credit will be automatically applied to your account within 4 days after spending the specified amount on any Kindle Books. We will notify you via email once your credit has been applied to your account.

How do I use my Kindle Book credit?
Your £3 Kindle Book credit is automatically redeemed on your next Kindle Book purchase. Any Kindle Book sold on Amazon.co.uk is eligible for this credit.

When does my Kindle Book credit expire?
Your Kindle Book credit expires at 11.59 PM (BST) on 11 July, 2020.

And terms and conditions:

Spoiler:

Terms and Conditions
• This is a limited-time offer. The offer is non-transferable and may not be resold.
• To receive the promotional credits, you must: (1) activate the offer by clicking on "Get offer" at any time before 11.59pm (BST) on 11 June, 2020 and (2) spend £10 or more on any one or more Kindle Books before 11.59pm (BST) on 11 June, 2020. (Redemption Steps).
• Within 4 days of completing the Redemption Steps, the promotional credits will be attributed directly to your customer account and automatically applied to your next qualifying Kindle Book purchase. You will receive an e-mail from Amazon confirming that the promotional credit has been applied to your customer account. The e-mail will also provide instructions on how to redeem the promotional credit.
• The promotional credits will expire at 11.59pm (BST) on the 11th of July. You can view your available promotional credit balance on any Kindle Book detail page. Confirmation that the promotional credit has been applied to a Kindle Book purchase will appear on the Order Summary Page. You will not need to enter a promotional code during checkout for the promotional credit to apply.
• The offer only applies to eligible Kindle Books sold by Amazon Media EU Sàrl at the website www.amazon.co.uk (the “Website”). The offer does not apply to Kindle Books sold on other Amazon websites.
• Use of the promotional credit requires an Amazon.co.uk account and acceptance of the Amazon Kindle Store Terms of Use.
• Purchaser will be responsible for the final price of an Kindle Book after the promotional credit is applied to that title.
• The promotional credit will not reduce the price of the items to which it is applied, though it will automatically reduce the amount you pay.
• This offer is only to customers located in the Great Britain, Guernsey, Jersey, Gibraltar, and Isle of Man.
• If any of the Kindle Books purchased using this promotional credit are returned, your refund will equal the amount you paid for the Kindle Books. The promotional credit will not be available for re-use. All refunds are subject to applicable Amazon refund policies.
• This offer may not be combined with other offers or other promo codes.
• If you violate any of these Terms and Conditions, the offer will be invalid.
• This credit can be used on multiple qualifying Kindle Book titles, in multiple transactions, up to a maximum benefit of 3.00 GBP.
• Amazon.co.uk reserves the right to modify or cancel this offer at any time.
• Each promotional credit has no cash redemption value.
• Unlike Amazon.co.uk Gift Cards, you will not be able to view any unused promotional codes or promotional rewards in the Your Account section of www.amazon.co.uk.