Mercury API
Mercury is a fintech platform delivering business banking, payments, treasury, corporate cards, and accounting automation for startups and scaling companies. A resilient API lets you programmatically pull accounts, balances, transactions, recipients, cards, and invoices—and push actions like ACH transfers, wire payments, bill pay, and invoice creation—back into Mercury, including the surfaces beyond its official token-scoped REST API.
What is Mercury?
Mercury is a fintech platform that provides business banking, payments, and financial management tools for startups and scaling companies. Customers use Mercury to run checking and savings accounts, earn yield through Treasury, issue corporate credit and debit cards with spend controls, send wires and ACH, pay bills, send invoices and receive payments, and automate accounting and reconciliation—backed by FDIC insurance through partner banks and integrations with QuickBooks, Xero, and NetSuite.
Core product areas include:
- Banking (business checking and savings, FDIC insurance through partner banks)
- Treasury (yield on idle balances via Mercury Treasury advisory)
- Corporate Cards (credit cards with cashback, instant virtual cards, spend controls and approvals)
- Payments (USD wires, ACH transfers, bill pay with AI recipient recognition)
- Invoicing & Receivables (free invoicing, payment acceptance, direct receipt)
- Accounting Automation (AI categorization, receipt matching, QuickBooks/Xero/NetSuite sync)
- Lending (working capital loans and venture debt)
Common data entities:
- Accounts, Balances, Sub-accounts, Statements
- Transactions, Postings, Categories, Receipts
- Recipients, Payees, ACH and Wire Transfers
- Cards, Spend Limits, Approvals
- Invoices, Bills, Payments, Disbursements
- Treasury positions and yield activity
The Mercury Integration Challenge
Mercury ships a clean token-scoped REST API, but covering the full breadth of how teams actually operate inside Mercury—and keeping integrations stable—still takes work:
- OAuth2 approval gate: Building integrations on behalf of other Mercury customers requires submitting a form and prior approval before access is granted
- Partial endpoint coverage: The public API centers on accounts, transactions, recipients, and payments—card controls, invoicing, treasury, and approvals are surfaced unevenly across versions
- Token security and rotation: Single-view API tokens with IP allowlisting require careful vaulting, scoping, and rotation in headless automation
- Payment workflow nuance: ACH, wire, and bill-pay flows carry distinct recipient, approval, and effective-date semantics that generic clients mishandle
- Reconciliation depth: Categorization, receipt matching, and accounting-sync state live across portal features that aren't fully exposed as first-class API objects
- API versioning drift: v1 and v2 surfaces evolve, so integrations need monitoring to absorb endpoint and schema changes without breaking
How Supergood Creates Mercury APIs
Supergood combines Mercury's official REST API with authenticated session flows to deliver a single resilient API layer that spans banking, payments, cards, invoicing, and treasury for your Mercury workspace—without waiting on OAuth2 partner approval for first-party access.
- Handles API token auth, OAuth2, and MFA-protected sessions securely with vaulting and rotation
- Maintains session continuity with automated refresh and change detection across API versions
- Normalizes responses across Accounts, Transactions, Recipients, Cards, Payments, and Invoices so you integrate once
- Respects spend controls, approval policies, and token scopes to ensure compliant, auditable access
Use Mercury with AI agents: Mercury MCP Server →
Getting Started
- Schedule Integration Assessment
Book a 30-minute session to confirm your accounts, payment flows, and authentication model.
- Supergood Generates and Validates Your API
We deliver a production-ready Mercury adapter tailored to your workspace, token scopes, and approval policies.
- Deploy with Monitoring
Go live with continuous monitoring and automatic adjustments as Mercury's API and product surfaces evolve.
API Endpoints
Authentication
/authenticateAuthenticate to a Mercury workspace using API token or OAuth2 and obtain a scoped session for downstream calls.
Accounts
/accountsList accounts and sub-accounts with current balances, status, and routing details.
Transactions
/transactionsRetrieve transaction history for an account with filters for date range, status, and category.
Recipients
/recipientsList saved recipients and payees with ACH and wire payment details.
Payments
/create_paymentInitiate an ACH or wire transfer to an existing recipient with amount, effective date, and memo.
Invoicing
/create_invoiceCreate and send an invoice with line items, payment methods, and recipient details.
Use Cases
Sync banking and transaction data into your stack
- Pull accounts, balances, and full transaction history into a warehouse or finance dashboard - Stream new transactions, postings, and categories to BI, FP&A, and spend-analytics tools - Reconcile receipts and statements across accounts for a unified cash view
Automate payments and treasury operations
- Initiate ACH and wire transfers to existing recipients without portal clicks - Schedule bill pay and route approvals through your own workflow engine - Monitor treasury positions and yield activity for cash management
Power invoicing and accounts receivable
- Create and send invoices programmatically with flexible payment methods - Track invoice status, payments, and direct receipts into Mercury accounts - Push paid-invoice and disbursement events into accounting and CRM systems
Manage cards and spend controls
- Provision virtual cards and set spend limits and approval policies via API - Sync card transactions and auto-attached receipts to expense systems - Surface policy violations and pending approvals to finance workflows
Technical Specifications
Authentication
API token (basic auth) and OAuth2 bearer tokens handled in a managed, scoped session
Connectivity
Mercury's official v1/v2 REST API plus authenticated session flows for surfaces not fully exposed publicly
Response format
Normalized JSON across Accounts, Transactions, Recipients, Cards, Payments, and Invoices objects
Rate limits
Adaptive throttling tuned to your workspace to stay within Mercury API limits
Session management
Automatic token refresh, OAuth2 re-auth handling, and credential rotation
Data freshness
Near real-time pulls for balances, transactions, and payments with optional scheduled batch syncs
Security
Encrypted credential vault, scoped tokens, IP allowlisting, and SOC 2 Type II-aligned controls
Webhooks
Event-style callbacks for new transactions, payment status changes, and invoice events
Latency
Sub-second reads on cached entities; multi-second writes when initiating ACH, wire, and bill-pay transactions
Throughput
Horizontally scaled workers sized to high-volume transaction and payment processing
Reliability
Retry, backoff, and idempotency keys for payment initiation and transfer transactions
Adaptation
Continuous monitoring of Mercury v1/v2 API releases and product surface changes for configuration drift
Frequently asked questions
Mercury's public API centers on accounts, transactions, recipients, and payments. Supergood unifies those endpoints with the surfaces that are exposed unevenly—card controls, invoicing, treasury, and approvals—into a single normalized layer, and absorbs v1/v2 versioning so your integration doesn't break.
No. For first-party access to your own Mercury workspace, Supergood works with your API token or OAuth2 session directly. The OAuth2 approval form is only needed when building integrations consumed by other Mercury customers, which Supergood can also support.
Yes. Supergood supports initiating ACH and wire transfers to existing recipients, with amount, effective-date, memo, and approval handling, plus idempotency keys to prevent duplicate payments.
Tokens are stored in an encrypted vault with scoped permissions, IP allowlisting, and automatic rotation. Supergood operates within your existing token scopes and approval policies for compliant, auditable access.
Yes. Invoices, payments, and direct receipts are exposed through the same normalized surface, alongside treasury positions and yield activity, so receivables and cash management sit beside banking and payment entities.