TL;DR
For US equities at retail scale in 2026: Polygon.io Stocks Advanced ($199/mo) wins for most flat-rate real-time workloads. Alpaca free IEX is the correct default for paper-trading research if you can tolerate partial volume. Tiingo wins for long-horizon research built on EOD + fundamentals at $10/mo. Databento wins for tick + L2, but metered pricing scales aggressively — model it before committing. FMP and Alpha Vantage sit in "budget with caveats" territory. Full pricing tiers and a live scenario calculator: /tools/data-vendor-tco/.
Methodology
All pricing reflects list rates on vendor pricing pages as of 2026-04-20. Enterprise + negotiated tiers are out of scope. Scenarios: small (≤50 symbols), medium (~500), large (~2,000), all US equities (~10,000). Resolutions tested: daily, 1-minute, 1-second, tick, L2. See /methodology/data-vendor-tco/ for the full rate table, assumptions, and limitations.
The headline table
| Vendor | Cheapest tier w/ real-time | Monthly | Resolutions | Options | Futures |
|---|---|---|---|---|---|
| Polygon.io | Stocks Advanced | $199 | daily → tick | no (equities server) | no |
| Alpaca | Algo Trader Plus | $99 | daily → tick | yes | no |
| Databento | Metered | ~$125 (medium-univ, minute) | daily → L2 | limited | yes |
| Tiingo | Power | $50 | daily + minute | no | no |
| FMP | Ultimate | $79 | daily → second | no | no |
| Alpha Vantage | Premium 600 | $250 | daily → second | no | no |
| Alpaca (free tier) | IEX-only | $0 | daily + minute | no | no |
Numbers reflect pricing as of 2026-04-20. Verify on the vendor page before committing.
Who wins for which profile
Profile: paper-trading researcher, zero budget
Alpaca free IEX + Tiingo Starter ($10/mo) for fundamentals. Total: $10/mo. Limitations: IEX is a subset of consolidated volume (roughly 2-5%), so backtests on it are partial. Fine for directional idea generation; not fine for execution-sensitive strategies.
Profile: swing trader, ~500 symbols, medium-frequency
Polygon.io Stocks Advanced ($199/mo). Real-time across the full SIP tape. Unlimited API calls. No options coverage — if you need options, pivot to Alpaca Algo Trader Plus ($99/mo) or layer on OptionsEngine / CBOE direct.
Profile: fundamental investor, long-horizon
Tiingo Power ($50/mo). EOD + fundamentals + news in one tier. Limitations: no real-time, no options. Pair with FMP Starter ($14/mo) if you need earnings call transcripts.
Profile: microstructure / HFT-curious retail
Databento metered (~$100-500/mo depending on universe + resolution). Only realistic option for tick + L2 at retail scale. Budget carefully — metered billing punishes speculative re-queries. Verify with Databento's quoting tool before subscribing.
Profile: options-first retail trader
Alpaca Algo Trader Plus ($99/mo) or tastytrade API. Polygon.io does not sell options data on the Stocks Advanced tier; it's a separate "Options Advanced" tier at a higher price.
Gotchas + caveats
- IEX tape vs SIP tape. Alpaca's free tier is IEX-only. IEX handles roughly 2-5% of total US equity volume. For low-frequency research on large-cap names, IEX is fine. For microstructure, small-caps, or anything execution-sensitive, you need SIP — which means paying for it.
- Databento's metered pricing. The calculator models typical retail spend at ~$125/mo for a medium universe on minute bars. Real spend varies ±50% depending on schema, delivery mode, and query patterns. Sandbox free credits are limited; production spend scales.
- Polygon.io's "unlimited API calls". Rate-limited by HTTP connection, not quota. Parallel streaming + bulk historical pulls can still get you throttled.
- Alpha Vantage's rate limits. Premium 75 allows 75 calls/minute. Premium 600 allows 600. For a 500-symbol scan, you'll hit that limit without batching.
- FMP's historical depth. Starter limits to 5 years. Premium removes the cap. Check your backtest window before subscribing.
The MCP angle
If your research stack uses MCP, consider vendor MCP server coverage:
- Polygon.io ships an official MCP server (read-only, Apache-2.0). Grade A in the Finance MCP Directory.
- Alpaca ships MCP V2 with 61 actions including execution. Grade A. The idempotency support is a distinguishing feature vs community alternatives.
- Databento has a community MCP server (grade B) — read before wiring to production.
- Tiingo, FMP, Alpha Vantage do not ship official MCP servers. Community wrappers vary in quality.
What we'd recommend today
The combo that shows up repeatedly in retail algo threads:
- Data: Polygon Stocks Advanced (real-time) or Alpaca Algo Trader Plus (if you also trade on Alpaca)
- Fundamentals: Tiingo Power
- Options (if needed): Alpaca options surface (included in Algo Trader Plus)
- MCP layer: Alpaca MCP V2 + Polygon MCP (both grade A)
Total: $250–300/mo for a mature single-operator stack. Budget workers can start at $10–50/mo (Tiingo + Alpaca free) and scale up as the strategy demands it.
Calibrate for your exact workload
The flat table above is a starting point; your actual cheapest vendor depends on your universe, resolution, and real-time need. The Data-Vendor TCO Calculator takes those inputs and returns a ranked list of qualifying vendors for your scenario. Use it before subscribing.
Sources
- Databento pricing (accessed 2026-04-20)
- Polygon.io pricing (accessed 2026-04-20)
- Alpaca Markets data plans (accessed 2026-04-20)
- Tiingo pricing (accessed 2026-04-20)
- FMP pricing (accessed 2026-04-20)
- Alpha Vantage premium (accessed 2026-04-20)
- Alpaca MCP Server V2 (accessed 2026-04-15)
- Polygon MCP Server (accessed 2026-04-10)
Editorial independence
AI Fin Hub Research maintains editorial independence across sponsor relationships. Vendor placements in tools and comparators are not altered by sponsor payments. Disclosures at /sponsor-disclosure/.