Mercury API
Mercury offers a self serve REST API on every plan covering accounts, transactions, recipients, payments, cards, treasury, and invoicing, plus HMAC signed webhooks, a CLI, and OAuth for partner apps. Tokens are per user and scoped; write scopes require IP allow listing.
Frequently asked questions
Mercury scores D+ on the API Report Card. Mercury offers a self serve REST API on every plan covering accounts, transactions, recipients, payments, cards, treasury, and invoicing, plus HMAC signed webhooks, a CLI, and OAuth for partner apps. Tokens are per user and scoped; write scopes require IP allow listing.
Without a usable official API, teams fall back on manual exports, file drops, or one-off vendor integrations. The other option is an unofficial API layer like Supergood that automates the authenticated web app directly.
Mercury is an online business banking and financial-operations platform built for startups, scaling companies, and SMBs.
Vertical: Financial Services, specifically business banking, treasury, and spend management for startups and SMBs (a fintech 'neobank' wrapping FDIC-insured partner banks). Founders open a Mercury account during company formation (often via Stripe Atlas or Clerky), deposit their seed/Series funding, and use Mercury as the primary operating account: ACH and wires to vendors, payroll runs (via Gusto/Rippling/Deel that pull from Mercury), corporate cards issued to the team with category and per-vendor spend controls, Mercury Treasury to park idle cash in money-market funds and T-bills, Mercury Invoicing to bill customers, AI bill pay to triage and pay vendor invoices, and the accounting integrations to sync every transaction into QuickBooks Online, Xero, or NetSuite.
Mercury reports 300,000+ entrepreneurs/companies on the platform, $156B in payment volume in 2024, ~$500M revenue in 2024, ten consecutive profitable quarters by Q1 2025, and a 4.9 Apple App Store rating.
Yes, for any company that banks with Mercury, it is the system of record for the entire cash and payments stack: every deposit and withdrawal, every ACH and wire (inbound and outbound), every check, every corporate-card swipe with merchant/category metadata, every Treasury sweep and money-market position, every recipient/vendor and approval policy, every issued/virtual card with controls, every invoice generated and paid through Mercury Invoicing, every AI-categorized bill in the AP queue, every accounting-sync mapping to QuickBooks/Xero/NetSuite, and full month-end statements.
Founded 2017 in San Francisco by Immad Akhund (CEO, ex-Heyzap), Max Tagher, and Jason Zhang. Launched publicly in 2019 with Evolve Bank & Trust as the initial partner bank (via Synapse).
Payment endpoints only support transfers to existing recipients, you cannot programmatically pay a new vendor in one call; the recipient must be created and (depending on amount/policy) approved first. Write-scope tokens require IP allow-listing, complicating dynamic/serverless deployments where outbound IPs are not stable. Full sourced list under Sources below.
Common alternatives include Brex, Ramp, Rho, Bluevine, Relay, Novo. Graded alternatives appear under "More from the report card" below.
Grades measure one thing: can a customer's engineering team get their own data out programmatically? We check six things (whether a real API exists, how access is gated, data coverage, auth quality, docs and developer experience, and stability) and roll them into a letter grade. Grades get re-verified, and they only move on evidence.
Yes. Supergood maintains an unofficial Mercury API and MCP server so AI agents and internal tools can read and write Mercury data. See the Mercury integration docs at supergood.ai/docs/mercury-api.