What UniPay is

UniPay is a bill-payment gateway. It sits between the organisations that raise bills and the ones that collect payment, and gives each side one standardised connection instead of a bespoke integration per partner.

You are a…	Examples	You…
Service provider	Councils, utilities, statutory bodies	Publish bills and collect the payments made against them.
Payment processor	Banks, mobile-money operators, fintechs	Look up a customer’s bill, take their money, and tell UniPay what was paid.

Both are tenants of UniPay: each has its own credentials and sees only its own data. A processor integrates once and can pay the bills of every service provider on the gateway.

flowchart LR
    C([Customer]) -- pays --> PP[Payment processor]
    PP -- "look up bill · report payment" --> U[UniPay]
    SP[Service provider] -- publish bills --> U
    U -- payments feed --> SP
    U --- L[(Ledger)]
    class U unipay

How a payment flows

1. The service provider publishes its bills to UniPay — directly, or through the Axis Sync Engine beside its billing system.
2. A customer asks their bank or mobile-money operator to pay. The processor looks the bill up by bill number or by account, and shows the customer what they owe.
3. The processor takes the customer’s money in its own system, then reports the payment to UniPay with its own unique reference.
4. UniPay records the payment in a double-entry ledger whose entries are hash-chained, so a recorded payment can’t be silently altered.
5. The service provider collects its payments from UniPay’s payments feed into its own system, and the money is settled to its bank account.

UniPay never converts money: it records exactly what the customer tendered, and what obligation that settles. See Payment lifecycle for the whole journey, and Currencies for payments in a different currency from the bill.

About these docs

These docs describe the build of UniPay that serves them: the test environment’s docs describe the test environment, production’s describe production. The build identifier is at the foot of every page — quote it when you contact support.

Need them offline, or to attach to a tender? Download the guides as one PDF — generated from the same build, with code in cURL. The online docs add the endpoint-by-endpoint API reference and code in eight languages.

Next: Environments and access.