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August 11, 2026

How to Connect Square

Accept cards, Square Terminal, and online payments.

What you'll need

A Square account and an app in the Square Developer portal.

Step 1 — Create an app

Go to developer.squareup.com and create a new app under your account. The app gives you an Application ID, Access Token, and a default Location ID.

Step 2 — Copy credentials

Use the Sandbox credentials to test, and the Production credentials (access token starting with EAAA) to go live.

Step 3 — Connect in SellDesk

  1. Open Settings → Payments.
  2. Expand the Square card.
  3. Paste your Application ID, Access Token, and Location ID.
  4. Save changes and toggle Square on.

Tip

Find your Location ID in the app's Locations tab — it's needed to route charges correctly.