If you exceed the credits included in your plan, additional credits will be billed at your plan’s per-credit rate. For instance, on a 200-credit plan, using 210 credits means you'll be charged for the extra 10 credits at your plan's rate. If your plan costs $39 for 200 credits, each additional credit is $0.195, totaling $1.95 for the extra 10 credits.
PAYG plans do not incur overage charges. Instead, your API access will be suspended until you add more credits to your account.