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While Amazon is known for its year-round sales, deals on subscription programs like Kindle Unlimited don’t come around too often, especially outside of a big Prime Day-like official event.

It’s officially Prime Big Deal Days, a.k.a. October Prime Day, through the end of the day tomorrow, Oct. 8, and the deals don’t stop at physical products.

Right now, Amazon Prime members can get three months of Amazon’s library-like book subscription plan for free. Kindle Unlimited is normally priced at $11.99/month.

You’ll be able to read everything from trending BookTok titles to tried-and-true classics and save $36 in the process. Now that’s what we call a good deal!

Most deals, including the Audible deal and this Kindle Unlimited offer, are only for Amazon Prime subscribers. If you aren’t one already, you’ll have to be before the big sale starts, and who can resist a free trial? The 30-day trial will take you through the end of Prime Big Deal Days.

• Kindle Unlimited’s catalog changes often, with books coming off of and joining the service all of the time.

  That’s why we recommend borrowing books as soon as you see them, even if you don’t plan on reading them right away, because you never know when they might disappear from the service.

  However, once you borrow a book, it stays in your library until you return it, even if that book is no longer available to borrow on Kindle Unlimited.

  Not unlike a library, subscribers can borrow up to 20 books from Kindle Unlimited at a time. Access to select audiobooks and popular magazines is also included.

  Is KU Worth It, Though?

  Kindle Unlimited’s library is made up of over four million titles, per Amazon, and we’ve found that there seems to be a particular emphasis on romance novels and thrillers. If those are your preferred genres, it’s absolutely worth the subscription.

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Prime Big Deal Days FAQs

When Is Prime Big Deal Days 2025?

Prime Big Deal Days starts on Tuesday October 7 at 12:01 a.m. PT and runs through Wednesday October 8 at 11:59 p.m. PT.

Do I Have to be a Prime Member to Shop?

Only Amazon Prime members can take advantage of fall Prime Day’s deals and discounts, and other interested consumers can get a 30-day free trial to enjoy Prime Day deals (plus all the benefits of the subscription).

Prime Day vs. Prime Big Deal Days

Similar to Amazon’s July Prime Day sale, Prime Big Deal Days drops major discounts across two days, but with a bigger focus on pre-Black Friday holiday gift shopping.

What Deals Are Worth It?

From years of deal-hunting on Amazon Prime Day, we know from experience that the sale is the perfect time to save on a Kindle Unlimited or Audible subscription, add Prime Video subscriptions to watch your favorite shows, upgrade to a new TV or soundbar and find discounts on all kinds of  tech and Amazon best-sellers.

When is the Next Prime Day?

For those already wondering, Amazon hasn’t yet confirmed the dates for Prime Day 2026, but it’s safe to assume it will take place in mid-July like past sales. Shoppers should keep an eye out for Amazon’s Black Friday sales to officially kick off in November.

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Why Trust Decider Shopping

This article was written by Angela Tricarico, Commerce Streaming Reporter for Decider, the New York Post, and Page Six. Angela keeps readers up to date with cord-cutter-friendly deals, how to watch your favorite sports teams and movies on each streaming service and the very best in tech, like soundbars, to enhance your viewing experience. Not only does Angela test and compare the services, devices and merch she writes about, but she’s also a superfan specializing in the intersection of shopping, tech and pop culture. Prior to joining Decider and the New York Post in 2023, she wrote about streaming and consumer tech at Insider Reviews. 

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