Amazon's Prime Day has a problem: Almost everyone has Prime already

• Amazon launched Prime Day to get more shoppers to sign up for its Prime membership.
• Now, almost everyone who wants to be a Prime member already is.
• That's changing the kinds of deals you can expect to see during this year's Prime Day.

Amazon Prime Day has served its purpose well — perhaps a little too well.

Amazon launched Prime Day to get more people to pay for its membership, which includes benefits like free shipping and streaming TV shows.

On the eve of Prime Day 2026, though, it may have almost maxed out the addressable market for Prime, said Sky Canaves, a principal analyst for retail and e-commerce at EMARKETER, a sibling company of Business Insider.

Over 86% of online shoppers are already Prime members, according to EMARKETER. "There just isn't much growth to capture," Canaves said.

The retailer first held the shopping holiday in 2015. The company drew inspiration from Alibaba's November Singles Day sale in China. Jeff Bezos, Amazon's founder and the CEO at the time, signed off on Prime Day as a strategy "to try to add new members to Prime," according to the book "Amazon Unbound" by Brad Stone.

Back then, about 40 million US consumers had Prime memberships, according to Consumer Intelligence Research Partners. Some 10 years later, that number stood at 200 million.

This year's four-day Prime event will last from June 23 to June 26 — earlier than most other Prime Days, which have taken place in July.

As it approaches peak Prime membership, Amazon appears to be rethinking its Prime Day strategy, Canaves said. Namely, it's trying to get the Prime members it already has to order more.

This year, Amazon is using Prime Day to promote groceries and other essential products. Its preview of Prime Day deals includes hot dogs, Celsius energy drinks, and Korean beauty label Mamonde.

Those items tend to sell for less — and tend to be less profitable for Amazon — than electronics and other more expensive items that dominated Prime Day in its early years. They also function as a loss leader, however, getting customers to visit Amazon more frequently.

"Amazon is trying to capture more grocery sales in order to then sell more to its customers," Canaves said.

It has plenty of competition. Retailers from Target to Lowe's have created rival sales that, like Prime Day, boost sales during an otherwise slow time of year.

Almost 60% of Prime members who plan to shop on Prime Day also said that they plan to check Walmart's rival sale for deals this year, according to a survey of 1,000 consumers in April conducted by marketing agency Tinuiti.

Walmart also has its own paid membership, Walmart+, and has been adding delivery perks spanning restaurant meals and last-minute grocery orders.

Those offerings put it in competition with Amazon on Prime Day.

"A real battleground for them is on the grocery side and the delivery side," Canaves said.

Do you have a story to share? Contact this reporter at abitter@businessinsider.com or via encrypted messaging app Signal at 808-854-4501. Use a personal email address, a nonwork WiFi network, and a nonwork device; here's our guide to sharing information securely.