What "billed annually" means
A price shown as "$12 per user per month, billed annually" is usually charged as one payment for the whole year: $144 per user, upfront.
The monthly figure is a way of expressing the yearly price. It does not mean you can pay month by month at that rate.
The discount you get
Annual billing is typically cheaper than paying monthly for the same plan. The size of the saving varies by vendor and plan, so compare both options for your own team size.
On SpecEntry product pages, when a vendor lists both billing options, the pricing questions section shows the exact annual saving per user.
What you give up
Flexibility. If your team shrinks, you may keep paying for unused seats until renewal. If the tool turns out to be the wrong fit, you may not get a refund for the rest of the year.
Adding seats mid-year is usually allowed and charged pro rata, but removing seats often has to wait for the renewal date.
A simple decision rule
Choose monthly billing while you are still testing a tool or your headcount is changing fast. Switch to annual once the tool is clearly part of how you work and your team size is stable for the next year.
Always check the renewal date and the cancellation terms before committing.
Use it on real prices