Market data connections
What Is the Difference Between IEX and SIP?
IEX is a single U.S. exchange. SIP refers to consolidated tape reporting from eligible U.S. exchanges; available real-time and historical access depends on the Alpaca plan and feed.
What problem does this solve?
You want to understand why a market-data feed may not match another platform.
Quick answer
IEX is one exchange. SIP data consolidates eligible U.S. exchange reports through the consolidated tape. Alpaca account entitlements determine which feed is available.
Steps
- Check which feed your Alpaca account and selected app settings can use.
- Compare the same symbol, session, quote or trade field, and observation time.
- If a value differs, note the feed and session before comparing it with another platform.
What you should see
A single-exchange IEX view can differ from a consolidated SIP view because the exchanges represented and the reported observations differ.
If it still doesn't work
Review Alpaca's current Market Data FAQ and plan details. Avoid assuming that a software subscription includes an Alpaca data entitlement.
Screenshot or video
A real app capture will go here.
No screenshot or video has been approved for this topic yet. This reserved location will only show genuine Market Watch 360 material.
public/images/help/help-iex-vs-sip.pngNo video URL registeredOfficial sources
Still need help?
Tell us what you're seeing.
Include the app version and steps that reproduce the issue. Never include passwords, Alpaca API secrets, or payment-card information.