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Financial Data APIs for B2B
Bank data tells you where the money went. Accounting data tells you what it was for. How the two kinds of financial data API differ, and why most B2B products end up needing both.
What is a financial data API?
A financial data API is a programmatic interface that returns structured financial records to software. The term covers three different kinds of API: market data APIs for stock prices and company fundamentals, bank data APIs for balances and transactions shared with the account holder’s consent, and accounting data APIs for the books of a business, such as invoices, bills, ledger accounts and financial statements. Consumer apps mostly need bank data. B2B fintech products, such as lenders, spend management tools and finance automation software, usually need bank data and accounting data together, because the bank shows the cash and the books show what it means.
The three kinds of financial data API
They share a name, not a use case. Searching for a financial data API usually means one of these.
Market data APIs
- Data
- Stock prices, quotes, fundamentals and filings of public companies.
- Source
- Exchanges, regulators and data vendors.
- Built for
- Trading tools, portfolio trackers, investment research.
- Examples
- Financial Modeling Prep, Alpha Vantage, Finnhub, FactSet
Bank data APIs
- Data
- Balances, transactions and account details from a person’s or business’s bank accounts.
- Source
- Banks and other financial institutions, through an aggregator, with the account holder’s consent.
- Built for
- Account verification, payments, lending, personal finance.
- Examples
- Plaid, MX, Stripe Financial Connections
Accounting data APIs
- Data
- The books of a business: invoices, bills, payments, ledger accounts, journal entries, profit and loss, balance sheet.
- Source
- Accounting and ERP platforms such as QuickBooks, Xero, NetSuite and Sage Intacct.
- Built for
- B2B lending, spend management, AP and AR automation, FP&A, reconciliation.
- Examples
- Apideck Accounting API, or each platform’s own API
Bank data APIs vs accounting data APIs
Bank data and accounting data describe the same money from two sides. A bank transaction says that 4,200 dollars left the account on Tuesday. The accounting entry says it paid invoice 1048 from a supplier and belongs to cost of goods sold.
| Bank data API | Accounting data API | |
|---|---|---|
| What it describes | Money that moved through an account | How the business recorded and classified that money |
| System of record | The bank or financial institution | The accounting or ERP platform |
| Typical records | Balances, transactions, account and routing details | Invoices, bills, payments, ledger accounts, journal entries, aged receivables and payables, P&L, balance sheet |
| Who grants access | The account holder, signing in at their bank and picking accounts | An admin of the business, authorizing a connection to the accounting platform |
| What it answers | How much cash is there, and where did it go? | What is owed, what is due, and is the business profitable? |
| Direction | Read only for most products | Read and write: create invoices, post bills, book journal entries |
| Standards | FDX in North America, PSD2 and UK Open Banking in Europe | No shared standard: every platform has its own API and data model |
Why B2B products need both
Bank data alone works for consumer products, where the bank account is the whole financial picture. A business keeps a second record of every transaction in its accounting system, and most B2B workflows depend on that second record.
B2B lending and underwriting
Bank data shows cash on hand and how it moves. Accounting data adds what bank data cannot: open receivables, upcoming payables, margins and a balance sheet. Lenders that underwrite small businesses on both get a fuller picture than either source gives alone.
Reconciliation
Reconciliation is the act of matching bank transactions to entries in the books. It needs the bank side and the ledger side at once, which is why bank feeds into accounting platforms exist at all.
Cash-flow forecasting and FP&A
A forecast starts from current balances, then layers in invoices that will be paid and bills that will come due. Aged receivables and aged payables come from the accounting system, not the bank.
Spend management and card issuing
Card and expense platforms hold the transactions. Their customers want those transactions in the books, coded to the right ledger account, without manual exports. That is a write into the accounting system.
How financial data APIs work
Bank and accounting data APIs follow the same four steps. The differences are in who authorizes and whether you can write back.
- 1
Authorize
The data owner grants access. For bank data that is the account holder signing in at their institution. For accounting data it is a business admin connecting their accounting platform, usually through OAuth.
- 2
Normalize
Every bank and every accounting platform structures data differently. A good financial data API maps them to one schema, so an invoice from Xero and an invoice from NetSuite look the same to your code.
- 3
Read and write
Your product requests the records it needs. Accounting APIs also accept writes, so you can create invoices, post bills or book journal entries back into the customer’s books.
- 4
Stay current
Webhooks or scheduled refreshes tell your product when records change, so you are not polling every connection. Plan for revoked consent and expired tokens: they are normal, not edge cases.
Where Apideck fits
Apideck covers the accounting side of financial data. The Accounting API reads and writes invoices, bills, payments, ledger accounts, journal entries and reports across 50+ accounting platforms, including QuickBooks, Xero, NetSuite and Sage Intacct, through one data model and one authorization flow. Profit and loss, balance sheet, aged debtors and aged creditors reports come back in the same format on every platform that supports them.
The Bank Feeds API connects the two sides in the other direction. Card issuers, embedded banking and payout platforms use it to push their transactions into their customers’ accounting platforms, natively into 10 platforms such as Xero, NetSuite and Exact Online, and into QuickBooks Online through Intuit Bank Feeds in early access. Apideck and Plaid have signed a partnership, and the upcoming Plaid Core Exchange connector lists your platform on the Plaid network, so your account holders can link their accounts from thousands of Plaid-powered apps and accounting platforms. Apideck is a member of the Financial Data Exchange (FDX).
Apideck does not aggregate end users’ bank accounts, and the Plaid partnership does not change that: it carries data from your platform into the Plaid network, not from a customer’s bank to you. If your product needs to read a customer’s bank balances and transactions, pair Apideck with a bank data aggregator such as Plaid, MX or Stripe Financial Connections. Both sides run with the customer’s explicit permission, and Apideck’s cloud connectors pass data through in real time with zero data retention, so no copy of your customers’ books sits on Apideck infrastructure.
How to evaluate a financial data API
Whether you are choosing a bank data aggregator or an accounting API, the same questions separate a demo from a production integration.
- Coverage of the systems your customers actually use, by country, not a headline connector count.
- Read and write support per resource, not just per platform.
- A normalized data model with an escape hatch, such as pass-through requests and custom field mapping, for what the model does not cover.
- How data is served: live from the source on every call, or from a synced copy that can be stale.
- Whether the provider stores your customers’ financial records, and where.
- A hosted authorization flow, so you never handle customer credentials yourself.
- Webhooks for changes, and clear handling of revoked or expired connections.
- SOC 2 Type II, GDPR and data residency options that match your own customers’ requirements.
Financial data API FAQ
- What is a financial data API?
- A financial data API is a programmatic interface that returns structured financial records to software. The term covers three different kinds of API. Market data APIs return stock prices and company fundamentals. Bank data APIs return balances and transactions from bank accounts, with the account holder’s consent. Accounting data APIs return the books of a business, such as invoices, bills, ledger accounts and financial statements, from platforms like QuickBooks, Xero and NetSuite. Which one you need depends on whose data you want and what question it answers.
- What is the best API for financial data?
- It depends on the data. For public market data, developers commonly use Financial Modeling Prep, Alpha Vantage or Finnhub. For customer-permissioned bank account data, the established aggregators are Plaid, MX and Stripe Financial Connections. For the accounting data of private businesses, a unified accounting API such as Apideck connects to 50+ accounting platforms through one integration, instead of building against each platform’s API separately. B2B fintech products often need both bank and accounting data.
- What is an API in finance?
- In finance, an API (application programming interface) is how one financial system shares data or actions with another in a structured, permissioned way. Banks use APIs to share account data under open banking rules, payment providers use them to move money, and accounting platforms use them to let other software read and write a company’s books. APIs replaced screen scraping and manual file exports for most of these flows.
- What is the difference between a financial data API and an open banking API?
- Open banking APIs are one kind of financial data API: the kind that gives regulated, consent-based access to bank account data, under rules such as PSD2 in Europe or the FDX standard in North America. Financial data API is the broader term. It also covers market data APIs and accounting data APIs, which have nothing to do with open banking regulation.
- Can I get a company’s financial statements through an API?
- Yes, but which API depends on the company. For public companies, market data APIs return filed income statements, balance sheets and cash-flow statements. For private businesses, the statements live in their accounting platform, so you need an accounting API and the business’s permission. Apideck’s Accounting API exposes profit and loss and balance sheet reports, plus aged debtors and aged creditors, in one format on every platform that supports each report.
- Does Apideck aggregate bank account data?
- No. Apideck does not read end users’ bank accounts. If your product needs customer-permissioned bank data, use an aggregator such as Plaid, MX or Stripe Financial Connections. Apideck covers the accounting side: reading and writing accounting data across 50+ platforms, and pushing bank feed statements from your platform into accounting systems such as Xero, NetSuite and Exact Online through the Bank Feeds API. Apideck and Plaid have signed a partnership, but it works in that same direction: the upcoming Plaid Core Exchange connector lets platforms that hold accounts, such as card issuers and embedded banking providers, be linked from Plaid-powered apps.
- What is FDX?
- FDX (Financial Data Exchange) is the nonprofit standards body behind the FDX API, the open banking data standard used across North America. Banks and data providers use it to share account, balance and transaction data with apps the account holder has approved. Intuit and Plaid both read FDX-based data. Apideck is a member of FDX.
- Do financial data API providers store my customers’ data?
- Some do. Many providers sync records into their own database on a schedule and serve your requests from that copy. Others pass each request through to the source system in real time and keep no copy. Ask every provider which model they use, because it decides how fresh the data is and how much of your customers’ financial data sits with a third party. Apideck’s cloud connectors are real-time pass-through with zero data retention.
Keep reading
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