Instalment Payments with PrivatBank, monobank and A-Bank for WooCommerce

Instalment Payments with PrivatBank, monobank and A-Bank is a single WooCommerce payment method in which the buyer picks the bank themselves. PrivatBank takes them to its own page and offers 2–25 instalments; monobank doesn’t redirect anywhere at all — a push notification in the app, a confirmation, and the buyer is already on the thank-you page. The store extends no credit: the bank pays the full amount — at once, or in parts over the term with the PrivatBank PB programme (“funds over the term”).

This isn’t an “instalments button” off a banner. It’s a full cycle: signature verification of PrivatBank and monobank notifications, status reconciliation with the bank, a hold-and-capture flow, confirmation of goods handed over, and refunds.

Why a store needs this

Instalments are the cheapest way to raise the average order value in categories where price makes people hesitate: appliances, furniture, bicycles, tools, children’s goods. Instead of “too expensive, I’ll think about it”, the buyer sees “about 1,200 UAH a month” and buys today.

The store isn’t lending anything and takes on no risk: the bank pays out the full order amount at once, and the buyer’s ongoing payments are then a matter between the buyer and the bank.

The usual problem isn’t wanting instalments — it’s that PrivatBank and monobank have different APIs, different flows and different commission logic. So stores end up either setting up just one, or running two separate modules that don’t know about each other. Here, all three banks are one payment method with one log.

What it looks like for the buyer

A single payment method, “Pay in instalments”, appears at checkout. Choosing it shows the buyer a choice of bank: PrivatBank, monobank or A-Bank. Next to it is a hint, “about N UAH a month”, calculated from the order total, not from a single item’s price.

PrivatBank. After placing the order, the buyer is redirected to the bank’s page, chooses the number of instalments there, and confirms. They then return to the store.

monobank. No redirect at all. The buyer gets a push notification in the monobank app and confirms there, while the store shows a waiting page that brings the order to success on its own as soon as the bank responds. To the buyer, it looks as if payment happened right on the site.

Both the classic checkout and the block-based checkout work — no separate setup is needed for blocks.

A-Bank. Like monobank, no redirect: the buyer enters a phone number, gets a request in the Abank24 app and approves it there, while the store waits on its own page and completes the order by itself. A-Bank notifications are not signed, so the plugin changes the order only based on the bank’s answer to a status request.

What the admin gets

The payment method’s settings let you enable the banks you need. You can leave one bank, two or all three — the buyer will see exactly what you’ve enabled.

For PrivatBank, you choose the programme matching your agreement: II, PP, IA or PB. The programme determines who pays the bank’s commission: with II (Instant Instalment) it’s the buyer; with PP (Instalment Payment) and PB (Instalment Payment with funds credited over the term) it’s the store; with IA (promotional Instant Instalment) the store and the buyer split it 50/50. The module doesn’t decide this for you — it simply works according to whichever programme is in your agreement.

For monobank, you set the store ID and secret key, and choose the range of instalments within 3–25.

In the Pro version, this is joined by a log of applications across all banks: who, when, how many instalments, the application’s current state, and the bank’s reply.

Why reconciliation matters more than notifications

A bank’s notification can fail to arrive: the site was down for a minute, the host returned a 502, a firewall dropped the request. A module that relies solely on the notification leaves the order at “Awaiting payment” in that case, even though the money has already been charged.

Here it’s different. After the buyer returns (PrivatBank) or while they’re waiting (monobank), the module itself asks the bank about the application’s status. So the order closes out even when the notification got lost along the way.

A repeated notification duplicates nothing: if the bank sends the same result twice, the module processes it once. And a paid order can’t be sent to the bank a second time — an application for an already-paid order simply isn’t created.

What’s needed from the bank

An agreement is required. For PrivatBank that’s “Instalment Payment” or “Instant Instalment” — the bank issues a store ID and password. For monobank, it’s the “Purchase in Instalments” agreement, under which a store ID and secret key are issued. For A-Bank, it’s the “Plati chastynamy” agreement: a store ID, a secret key and a point of sale.

No agreement is needed for testing: PrivatBank and monobank have public sandboxes, and the module has test modes for them. So you can run the whole checkout, notifications and reconciliation before signing anything, and approach the bank with an already-working store. A-Bank has a test contour with a test store, but it works with the real Abank24 app, so the buyer’s number must belong to an A-Bank customer.

When the store gets paid

PrivatBank pays out the order amount once the application is approved, under your programme’s terms.

monobank charges the first instalment and pays the store the full amount right after approval. The instalment plan itself becomes active once the store confirms the goods have been handed over — in Pro this is done by a button in the log or automatically on a chosen order status.

A-Bank pays out under the terms of your “Plati chastynamy” agreement; the instalment plan becomes active once the store confirms the goods have been handed over.

Under the hood

Every PrivatBank and monobank notification’s signature is verified before the module does anything to the order — this isn’t an option that can be switched off; A-Bank notifications carry no signature and only trigger reconciliation with the bank. Keys are stored encrypted in the database.

Only a result reconciled with the bank changes the order status. A notification, to the module, is a signal to “go and check”, not a command to “mark as paid”.

The module doesn’t touch other payment methods and doesn’t override checkout: it registers as an ordinary WooCommerce payment gateway and lives alongside the rest.

How to install

1. Upload the archive via “Plugins → Add New → Upload Plugin” and activate it.

2. WooCommerce → Settings → Payments → “Pay in Instalments”.

3. Enable the banks you need and enter the credentials: for PrivatBank — store ID, password and programme; for monobank — store ID and secret key; for A-Bank — store ID, key and point of sale.

4. Turn on test mode and run an order through each bank’s test mode.

5. Turn off test mode — and you’re ready to accept payments.