If you did not explicitly set a billing limit in your account, you will just be charged overage. That means you will pay a slightly higher dollar per gigabyte price than your plan includes. You will also receive warnings by email, which will allow you to upgrade to more cost effective plans when that is possible.

For instance, our Startup plan comes at $69 per month with 40 GB included and $1.80 per additional GB. If you used up 40.8 GB, you would pay $69 + 0.8 × $1.80 = $70.44.