Is there a clearinghouse that doesn’t charge fees for processing 837P claim files for Cigna

Our behavioral health practice takes a lot different insurance plans. We work with five different clearinghouses to avoid paying any fees to process claim files for those payers. I need to find a clearinghouse that doesn’t charge a fee to process CIGNA claims. We’re evaluating adding Cigna insurance to our practice, but we don’t want to pay a fee per provider to process claims for Cigna. Has anyone found a clearinghouse that will process CIGNA claims without charging a fee?