Financial Modeling Prep vs Polygon (Now Massive): Which API Fits SEC and Fundamentals Data

FMP cells come from site.financialmodelingprep.com/pricing-plans and Massive cells from massive.com/pricing and massive.com/docs, all checked on 2026-11-02.

Polygon.io renamed itself Massive on October 30, 2025. Old polygon.io links redirect, and the old API host still works beside the new one, so most "Polygon" tutorials still apply. This page uses Massive for the current product.

The two come at SEC data from opposite sides. FMP is fundamentals-first: income statements, balance sheets, ratios, as-reported statements, filing lists, insider and congressional trades and, on its top plan, earnings call transcripts and 13F holdings. Massive is market-data-first: trades, quotes, aggregates and WebSockets across stocks, options, indices, currencies and futures, with financials as a $29 add-on and a newer set of parsed SEC filing endpoints.

Personal-use plans as of 2026-11-02, billed monthly (annual billing in brackets):

• Basic, $0: 250 calls a day, end of day data, profile and reference data.
• Starter, $29 ($19): 300 calls a minute, up to 5 years of history, US coverage, annual fundamentals and ratios, news.
• Premium, $69 ($49): 750 calls a minute, up to 30 years, UK and Canada, full fundamentals and ratios, intraday charts, corporate calendars.
• Ultimate, $139 ($99): 3,000 calls a minute, global coverage, earnings call transcripts, ETF and fund holdings, 13F holdings, bulk delivery.

Two conditions sit under the table. Each plan has a trailing 30-day bandwidth cap (500MB free, 20GB Starter, 50GB Premium, 150GB Ultimate). And "displaying or redistributing data sourced from FMP requires a specific Data Display and Licensing Agreement", so an app that shows FMP data to other people needs more than a personal plan. Commercial pricing is on a separate tab.

The endpoint list includes SEC filings by form type, symbol and CIK, the latest 8-K filings, as-reported statements, 10-K reports as JSON or XLSX, and Senate and House trading.

Massive prices by asset class. For US stocks, as of 2026-11-02:

• Stocks Basic, $0: 5 calls a minute, end of day data, 2 years of history.
• Stocks Starter, $29 a month ($288 a year): unlimited calls, 15-minute delayed, 5 years.
• Stocks Developer, $79 ($768): adds trades, 10 years.
• Stocks Advanced, $199 ($1,920): real-time quotes and trades, 20+ years, and Financials & Ratios included.

Financials & Ratios is also sold alone for $29 a month or $288 a year: cash flow, income statements, balance sheets and ratios, historical financials for 6.5k companies and current ratios for 4.4k tickers, since 2009. The plans shown are marked individual use only, with business pricing separate.

Its docs index lists SEC filing endpoints for 10-K sections, 8-K text and disclosure categories, Form 3 and Form 4 insider filings, 13-F holdings, risk factors and an EDGAR index, plus a free-float endpoint and an MCP server that signs in over OAuth.

Signal8 is a third option, and we make it. Its API and hosted MCP server come with Signal8 Pro ($59 a month or $588 a year as of 2026-11-02): 120 requests a minute, 10,000 a day and 3 keys.

It is narrower than either vendor on market data and deeper on what small-cap filings say. The docs list endpoint groups for companies, dilution, EDGAR, insider intelligence, market data, congressional and executive branch trades, cash position and reverse splits. Dilution figures (warrants, convertibles, shelfs, ATMs) are tied to the 8-K, 10-Q or prospectus they came from, insider data covers Form 4 filings with cluster-buy detection, and institutional data comes from 13F filings. Through MCP, an assistant such as Claude can call 109 tools in plain English.

• No free API tier. Both FMP and Massive have $0 plans; Signal8's API needs Pro.
• Daily cap. 10,000 requests a day, where Massive's paid stock plans list unlimited calls.
• US-listed companies only. Options, futures, forex and global fundamentals, which Massive or FMP Ultimate cover, are not listed in Signal8's API docs.
• No streaming or bulk delivery. Signal8's docs list no WebSocket or flat-file delivery.
• No published history depth for financials. FMP states up to 30 years on Premium and Massive states financials since 2009. Signal8 publishes no equivalent figure, so check the endpoint before relying on long histories.

Financial Modeling Prep fits if you need statements and ratios across many years and countries at a low price, with congressional and insider trades from the same key.

Massive (formerly Polygon) fits if prices come first: real-time or historical trades and quotes across asset classes, with financials and parsed filings added on.

Signal8 fits if your questions are about small-cap dilution, cash runway, insider and congressional trades, and you want them in an AI assistant through MCP.

The Academy's API quickstart and MCP with Claude guides show a first call.