The discount is built into the credit packs, so you never have to ask for it. Here's the full ladder: 1,000 for $5, 10,000 for $25, 50,000 for $89, 100,000 for $139, 500,000 for $549 and 1,000,000 for $949. Per address, that runs from $0.005 down through $0.0025, $0.00178, $0.00139 and $0.0011 to $0.00095. The pricing page shows the same table.
You don't lose the discount by buying big and using slowly. Credits never expire, so a team that buys 100,000 for $139 can spend them over a year of campaigns. Kickbox and Hunter both expire credits after 12 months (read 24 September 2026), which turns a bulk buy into a deadline. Our answer on credit expiry compares the rules.
Monthly plans take a further 15% off. The 10,000-credit plan is $21 a month against $25 pay-as-you-go, and the 100,000-credit plan is $118 against $139. Unused credits roll over while the plan is active, so a quiet month doesn't cost you anything.
Two billing rules make the real discount bigger than the ladder shows. Unknown results cost nothing, and a duplicate of an address already in the same batch costs nothing. You pay for the answers ZapBounce got from a mail server, so a messy file with repeats costs less than its row count suggests. See which verifiers charge for unknowns.
To pick a tier, count the unique addresses you'll verify in a year and buy the pack that covers them. If you're near the top of the ladder, the one-million answer walks through the maths for the biggest tier.
Related questions
Is there a discount for buying more email verification credits?
Yes. The price per check falls at every ZapBounce tier, from $0.005 at 1,000 to $0.00095 at 1,000,000. A monthly plan takes another 15% off the same credits.
Do I need to talk to sales to get volume pricing?
No. All six ZapBounce tiers, up to 1,000,000 checks for $949, are listed on the pricing page and bought at checkout. There's no contract and no minimum.
Do agencies get a separate rate?
Agencies buy on the same ladder and reach the lower tiers faster by pooling client work in one pack. An account holds several API keys, each with its own label, so you can keep client jobs apart.
Do bulk credits expire if I don't use them?
No. ZapBounce credits never expire, so a 500,000 pack for $549 keeps its value until you've used every check.