Typical mapping for IB equity symbols?

I've seen plenty of posts with people complaining about having to map IB symbols but I can't find any information about what typical mapping is done. I assume SMART for execution but which exchange are people using for the data? I want to use IB for both data and order placement for SP500 symbols and have an IBKR pro account with no add-on data subscriptions.

Hello ZaphodB,

Symbol mapping can be required in one of the following cases:

1. Your data source is not the same as your broker. For example, you plot IQFeed data and trade with Interactive Brokers broker profile. Data source symbols should be mapped to broker symbols.
2. You trade continuous futures. Continuous contracts should be mapped to front-month contracts. For example, @ES should be mapped to ESZ2.
3. You trade custom futures. Custom futures should be mapped to corresponding front-month contracts.

If these are not your cases, symbol mapping is not required.
For more info please see this page.

Ok, thanks. I think the issue may be that people don't trust IB data so they're often using another data source and that's where all the posts about mapping with IB come from. I was planning on using 5 minute bars so hopefully IB data will be good enough for that.