Connecting
Most affiliate platforms offer a Shopify app or a pixel you add through checkout settings. Always place a real test order and confirm order value and currency arrive correctly.
Where possible use the server-side or webhook integration: it is more stable than a script that browser settings can block.
Voucher codes and checkout apps
Discount codes and upsell apps cause most measurement errors: they change the order total after tracking fires, or overwrite attribution.
Decide whether commission applies to the paid order value, excluding discount, VAT and shipping — and put it in your programme terms.
Multiple currencies and markets
Shopify Markets shows prices in local currency. Make sure your affiliate software converts to one reporting currency, otherwise you compare apples with pears.
Check per market that the correct landing page is tracked and that your domain or subfolder structure doesn't break the cookie.
Product feed
Publishers work best with a feed: title, price, stock, image, category and deeplink. A fresh feed generates more placements than the prettiest banner.
Refresh at least daily and keep stock status current; nothing loses trust faster than sold-out products in comparison sites.
Test before launch
Place a test order per market, with and without a voucher code, on mobile and desktop. The sale should appear in your affiliate dashboard within minutes.
Test a return as well: it must show as a declined transaction so you don't pay commission on returned orders.