Square APIs by Block, Inc. (Square)
Accept card and ACH payments inside web or mobile apps through Square's payments APIs and SDKs.
Payments for agents Official MCP server
＋ Build a stack with Square APIs Website Official pricing GitHub
Price
from $1
pay as you go, list price
Free tier
No
SDK downloads
—
npm square · PyPI squareup
Pricing
| Free tier | — |
|---|---|
| Cheapest paid plan | — |
| Usage price | 2.9% + 30¢ per card payment via payments APIs; API ACH transfers 1% ($1 min, $5 fee cap) (US) |
| Good to know | US rates; businesses processing over $250,000 a year may qualify for custom pricing. MCP server is in beta (remote at mcp.squareup.com/mcp or local npm package). |
From the official pricing page, checked Oct 10, 2026. Prices change: confirm before you buy.
Use it from an agent
| MCP server | Official: square-mcp-server |
|---|---|
| npm | npm install square |
| PyPI | pip install squareup |
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