IEX Cloud vs Polygon.io (2026) — Which Is Better?
Compare IEX Cloud and Polygon.io — features, pricing, pros and cons.
Fees, feature availability, and plan details come from each provider's current documentation. If you're about to act on this, confirm the specific numbers on the vendor's site first. Methodology →
Bottom Line
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
Polygon.io pricing, free tier limits, API features, and real-time market data plans compared for developers, algo traders, and fintech builders.
Data Coverage & Delivery Breakdown
| 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 | ✗ | ✗ |
Market-Data Head-to-Head
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.
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
- + Useful free tier for API testing and prototypes
- + Institutional-grade data quality
Cons
- - Real-time stock data requires the $199/mo Advanced plan
- - Can be complex for non-developers
- - Options and multi-asset use cases can change the total data budget
- - Less beginner-friendly than Alpha Vantage