If you're on metered billing (see Billing), you spend from a prepaid balance in Kenyan shillings (KES). Payments are handled by SMPLY PAY, a payments platform:
Your Deposits page shows both balances side by side: Nia Gateway credit (what your API requests spend) and your SMPLY PAY wallet (money that has arrived but hasn't moved into credit yet). It also lists your recent top-ups.
On the Deposits page, enter your M-Pesa phone number
(0712345678 or 254712345678) and an amount in KES, then choose Send
M-Pesa prompt. Your phone shows an M-Pesa prompt; enter your PIN to
approve it. Once the payment completes, your credit updates automatically.
Refresh the page to see it.
There's a minimum top-up for this method, shown on the page and on Pricing.
From your M-Pesa menu choose Lipa na M-Pesa → Pay Bill, and use the business number and account number shown on your Deposits page. The account number is unique to your wallet. Any amount you pay this way becomes credit. It can take a few minutes longer than an STK prompt to appear.
Top-ups are credited 1:1: a KES 500 payment becomes KES 500 of credit. There's no fee on top-ups.
Yes. A top-up is credited only after SMPLY PAY has settled the payment and the funds have actually moved, and each one is credited exactly once. If anything is interrupted along the way (a network blip, a restart), the gateway resumes it automatically within a minute. It never charges you twice or credits you twice. It also checks every wallet regularly, so even a payment whose confirmation was lost in transit is picked up.
You can still see your balances and history, but you can't start a new M-Pesa prompt until the account is reinstated.
If you've stored your own Anthropic key (BYOK), requests are billed by Anthropic directly, and you don't need to fund a balance at all.