IEX Cloud vs Polygon.io (2026) — Which Is Better?
Compare IEX Cloud and Polygon.io — features, pricing, pros and cons.
Quick Verdict
Higher Rated
Polygon.io (4.4)
More Affordable
IEX Cloud (Free)
IEX Cloud
IEX Cloud (retired Aug 2024) was a financial data API platform delivering 50+ institutional-grade datasets with real-time streaming and credit-based pricing for developers.
Polygon.io
Institutional-grade financial data API with real-time WebSocket streaming, tick-level data, and broad market coverage.
Our Analysis
Based on the data you've provided, here's the 150-200 word editorial analysis:
IEX Cloud and Polygon.io serve developers seeking institutional-grade market data, but they operate in fundamentally different market positions. IEX Cloud offered a transparent, credit-based pricing model with excellent documentation and sub-8ms WebSocket streaming—ideal for cost-conscious developers. Polygon.io delivers tick-level historical precision and generous free-tier access (5 req/min) with institutional-grade quality, but reserves real-time WebSocket streaming for the $199/mo tier. Both platforms supported backtesting, alerts, and broker integration, targeting similar use cases at different price points.
The critical differentiator: IEX Cloud was permanently retired August 31, 2024, making live adoption impossible today. Polygon.io remains operational with a clearer free-to-premium path—basic REST API access costs nothing, while institutional features require subscription. IEX Cloud's main advantage (affordability relative to Bloomberg) has become irrelevant; its unresponsive support and undisclosed surcharges on certain feeds reflected operational weakness.
For traders choosing today, Polygon.io is the only viable option. It best serves developers who can work within 5 req/min free limits initially, then upgrade to $199/mo for real-time data. If you need lower-cost alternatives to Polygon, consider Alpha Vantage or Finnhub rather than researching a defunct platform.
Feature Comparison
| Feature | IEX Cloud | Polygon.io |
|---|---|---|
| Rating | ★ 3.7 | ★ 4.4 |
| Starting Price | Free | Free |
| Free Tier | Yes | Yes |
| Markets | stocks, etfs, forex, crypto | stocks, options, forex, crypto |
| AI Analysis | ✗ | ✗ |
| Backtesting | ✗ | ✗ |
| Paper Trading | ✗ | ✗ |
| Price Alerts | ✓ | ✗ |
| Mobile App | ✗ | ✗ |
| API Access | ✓ | ✓ |
| Social Features | ✗ | ✗ |
| Broker Integration | ✗ | ✗ |
| Custom Indicators | ✗ | ✗ |
| Automated Trading | ✗ | ✗ |
| Trade Journaling | ✗ | ✗ |
| Performance Analytics | ✗ | ✗ |
| Risk Management | ✗ | ✗ |
| News Feed | ✓ | ✓ |
| Education Content | ✗ | ✗ |
IEX Cloud: Pros & Cons
Pros
- + Affordable REST API alternative to Bloomberg and Refinitiv for developers
- + Well-structured endpoints with excellent documentation and interactive explorer
- + Credit-based pricing model provided transparent, predictable costs
- + Real-time SSE streaming with sub-8ms average latency
- + Rules Engine enabled automated webhook and SMS alerts without custom code
Cons
- - Service permanently shut down August 31, 2024 — no longer operational
- - Incomplete ticker coverage with missing symbols reported by users
- - Customer support was frequently unresponsive to escalations
- - Some data feeds (e.g., delayed NASDAQ intraday) carried undisclosed third-party surcharges
Polygon.io: Pros & Cons
Pros
- + WebSocket streaming for real-time data
- + Tick-level historical precision
- + Generous free tier at 5 req/min
- + Institutional-grade data quality
Cons
- - Real-time data requires $199/mo plan
- - Can be complex for non-developers
- - Options data costs extra
- - Less beginner-friendly than Alpha Vantage