add_payment_info is a recommended ecommerce event in Google Analytics 4 that a website sends when a shopper submits their payment details during checkout. It marks the step between choosing delivery and completing the order, so you can see how many people reach the payment stage and how many of those go on to buy.
How add_payment_info works
GA4 has a standard sequence of recommended events for online shops. In a typical checkout they run in this order:
- begin_checkout when the shopper starts checkout;
- add_shipping_info when they choose a delivery option;
- add_payment_info when they submit a payment method;
- purchase when the order is confirmed.
The event takes the usual ecommerce parameters: currency (GBP for a UK shop), value, an optional coupon, an items array listing the products, and payment_type, which describes the method, such as card, PayPal, Apple Pay or a buy-now-pay-later option like Klarna. Platforms such as Shopify and WooCommerce plugins often send it automatically; custom sites push it into the data layer and fire it through Google Tag Manager.
The payment_type parameter should only ever be a label. Card numbers, names and billing addresses must never be sent to GA4.
Why it matters
The payment step is where many otherwise good checkouts fail. A shopper who has chosen delivery has shown strong intent, so a big drop between add_payment_info and purchase usually points to a specific problem: a card declined by 3D Secure authentication, a payment page that breaks on mobile, a missing wallet option or a surprise charge at the last moment.
With add_payment_info in place, a funnel exploration can show the drop at each step, broken down by device, browser or payment_type. A Glasgow gift shop might find that mobile shoppers choosing PayPal complete far less often than card users, which turns a vague “checkout problem” into one thing to test.
When the payment page is hosted elsewhere, such as a PayPal or Stripe page, the shopper leaves your domain. Without the right referral settings, the returning visit can start a new session credited to the payment provider rather than the original channel, which damages attribution.
If you also advertise on Facebook and Instagram, Meta has a matching standard event, AddPaymentInfo. Firing both from the same data layer push keeps your GA4 funnel and your ad reports describing the same step, so when purchases fall you can see whether the problem started at payment or earlier.
Common mistakes
- Firing the event when the payment page loads rather than when details are submitted, so it simply duplicates begin_checkout.
- Leaving out the items array, which GA4 needs to report products in the checkout.
- Sending value as text with a pound sign instead of a number.
- Putting card or personal details into parameters.
- Not listing payment providers as unwanted referrals, so sales are credited to them.
How to act on it
Place a test order and watch GA4 DebugView to confirm all four checkout events fire in order, each with currency, value and items. Then build a funnel exploration from begin_checkout to purchase and compare devices.
If the payment step loses more people than you would expect, test the payment journey yourself on a phone with each method you offer. Add payment providers to GA4’s list of unwanted referrals.
Finding where checkouts leak is a regular part of the ecommerce ads work I do for UK shops, because fixing the checkout can do more for return on ad spend than any change to the ads.