Amazon is raising the price on Prime memberships for customers who choose to pay monthly instead of the full year upfront. The cost is going up from $10.99 per month to $12.99, according to Recode.

While the $2 extra per month may not sound like much, it’s an 18 percent increase that works out to an extra $24 per year. That raises the total annual cost for monthly membership to $156, instead of the previous $132.

In other words, customers who subscribe to Prime on a monthly basis, either because they can’t afford the full annual price upfront, or choose not to commit to a year at a time, are now paying an even higher premium over the $99 annual subscription rate, which remains unchanged.