What happens when you run out: usually, a hard stop
Across 196 plan tiers, the most common answer to “what happens when the meter hits zero” is a hard stop — 103 tiers block you until you buy more or wait for the reset. Behind it, a long tail: overage you opt into (30); silence still — 27 tiers that simply don’t say; overage billed automatically by default (21), the one that turns a busy week into a surprise invoice; and a throttled cap (15).
A hard stop (highlighted) leads — run out and you’re blocked until you pay or wait for the reset. Auto-overage billed by default is the one that surprises you.
SoF · The AI Credit IndexBeyond the default, 19 tiers offer auto-recharge (your balance tops itself up — and bills) and 2 publish a hard usage cap as a multiple of the plan allowance (e.g. Zapier stops at 3× the task limit).
Included credits rarely roll over
Included credits expire (reset each cycle, no carry-over) on 111 of 196 tiers and roll over on just 39. Separately purchased top-up credits are treated more generously where vendors bother to say — never expiring on 29 tiers — but their policy is left unstated on 107, the most common case of all.
Included credits mostly expire each cycle; purchased credits are treated more generously — when vendors bother to state it at all.
SoF · The AI Credit Index“Unlimited,” with an asterisk
21 plan tiers market an “unlimited” allowance — and 20 of them carry fair-use fine print (relaxed or slow mode after a hidden cap, select models only, a first-year promo, or “unlimited” applied to something other than the metered resource). Genuinely uncapped is the exception, not the rule. Separately, 20 products run more than one credit type at once (e.g. fast vs. rollover vs. top-up balances, or image vs. video credits), so “your credits” can mean several meters that deplete in a set order.
Cancellation terms are captured per product (16 of 51 state what happens to credits when you leave) and surface per-row in the data.