Independent provider
If you are an independent provider, you can enter one rendering Type-1 NPI number and one billing NPI number; typically the same number. They could differ if you are credentialed and billing under a practice name instead of your individual NPI.
Practice group billing as a group
You can enter your rendering provider Type-1 NPI number as well as the billing Type-2 NPI number for the practice group if you are billing as a group under the organizational NPI.
Part of a practice group, but billing independently
If you are part of a practice group in DrChrono, but you want to bill out independently, you can enter your rendering NPI number as well as the billing NPI number. This is most likely the same as your rendering NPI number.
Exception
If you are in a practice group and have multiple tax IDs and billing NPI numbers to bill from, you must set up an office attaching the numbers you would like to use (typically this will be an organizational NPI number). To learn where to enter this information, refer to Entering in an additional NPI number and Tax ID for billing purposes.
When you schedule an appointment in an office with a billing NPI number and tax ID number associated with it, your claims are submitted under the billing NPI. This overrides the NPI number in the provider's account settings. This is useful if you need to bill multiple businesses as one provider.
If you have a specific payer that needs to be billed differently than the rest, you can make those changes per payer under Insurance Setup.