The four things
One payer offers many plans. One plan uses one or more networks. And an administrator’s name on a card tells you nothing about who bears the risk.
The distinction that matters most: fully-insured versus self-funded.
On a fully-insured plan, the insurance company bears the risk. On a self-funded plan, the dominant model for large employers, the employer bears the risk and the carrier is only an administrator.
The card looks identical. What differs is the governing law: self-funded employer plans are governed by ERISA, with state insurance law largely preempted. That means your state’s prompt-pay statute and external review process may simply not apply to a large fraction of your commercial claims.
Determine funding status before you escalate or cite a state statute. See Payers vs insurance companies.
How the profile pages are structured
Every payer profile follows the same template, so you can navigate any of them blind:Finding a payer’s ID, portal, and forms
1
Payer ID, use your clearinghouse's payer list
Payer IDs are clearinghouse-specific. The same payer can have different IDs at different clearinghouses, and separate IDs for professional versus institutional claims. Your clearinghouse’s published payer list is the canonical source, not a third-party table, and not this site.This is also why switching clearinghouses requires remapping every payer.
2
Portal, start at the payer's provider site
Many payers use Availity as their provider portal even when Availity is not your clearinghouse.
3
Enrollment forms, the payer's provider enrollment page
See Payer enrollment and submission links for the index.
4
Medical policies and companion guides, the payer's own documentation
These outrank any third-party summary, including this one. A payer’s published medical policy is what you cite in an appeal.
The payer landscape in brief
See The US payer landscape.
Enrollment priority
1
Identify actual market share in your area
Not nationally. In most markets the local Blue is the largest commercial payer.
2
Start Medicare and Medicaid first
Slowest, and no contract negotiation.
3
Then the largest commercial payer in your market
4
Check panel status before investing months
“Panel closed” is a real answer.
5
Request the fee schedule before signing anything
The multi-entity multiplier
Everything in this section is per entity. Each PC is a separate Tax ID with its own contracts, its own credentialing, and its own EDI, ERA, and EFT enrollments with every payer.
This is why clearinghouse enrollment support quality is the criterion worth weighting most heavily. See Choose a clearinghouse.