Kindle Unlimited vs Prime Reading

Kindle Unlimited is a separate paid subscription. Prime Reading is a benefit inside Amazon Prime. Having Prime does not give you Kindle Unlimited, and the two draw on different catalogs.

The practical difference

The reading benefit bundled with Prime is deliberately modest — a rotating selection, with a small number of titles held at once. Kindle Unlimited is the larger catalog with the higher borrowing limit, which Amazon states as up to 20 titles at a time with no due dates. One is a perk designed to be pleasant; the other is a product designed to be someone's main source of reading.

We are describing the shape rather than quoting current catalog sizes or Prime's exact borrowing limit, because Amazon changes the Prime benefit line-up regularly and we could not confirm the current figures against a page we can read. What your own Prime account includes right now is shown in your account — see what Prime actually includes for how to check it properly.

How to decide

If you already pay for Prime, the sequence is obvious and almost nobody follows it: use the Prime reading benefit first. It costs you nothing additional, and a month of it tells you exactly what you need to know. If you keep running out of things you want to read, the paid subscription is solving a real problem for you. If you never got through the Prime selection, a bigger catalog is not what was missing.

If you do not have Prime, this comparison mostly is not yours to make. Buying Prime for its reading benefit alone would be an odd way to arrive at an ebook subscription, and the decision you actually want is on whether Kindle Unlimited is worth it.