Sending Claims and Receiving ERA 835s through Clearinghouses Other than Optum

Some providers want to receive 835 ERAs from Tendo Marketplace (MDsave) but don’t use Optum for their clearinghouse. Tendo doesn’t work directly with any clearinghouses except Optum, and other clearinghouses may say that they don’t work with Tendo Markeplace for that reason.

Tendo can receive claims from other clearinghouses as well as through Optum, but we don’t have visibility into that process until we receive the claims. Request of your clearinghouse that MDsave be created as a payer with our payer information. Your clearinghouse then should be able to establish a connection with Optum to allow claim delivery from you to your clearinghouse to Optum to Tendo.

For 835 ERAs, request that your clearinghouse establish a connection with Optum so that you can receive 835s from MDsave. The ERAs should be transmitted from Tendo to Optum to your clearinghouse to you. Tendo doesn’t have any visibility into this process. We can only see that we delivered an 835 to Optum.

As a payer, Tendo can’t establish this connection on your behalf. You must initiate the request.

Here is an example of how you can work with a clearinghouse other than Optum to send claims to MDsave and receive 835 ERAs from MDsave. This example uses Waystar as the provider’s clearinghouse.

Waystar and Optum are separate clearinghouse networks so the following routing needs to be established between Waystar and Optum.

  • 837 Claims - ➡️ Provider → Waystar → Optum → MDsave
  • 935 ERAs - ⬅️ MDsave → Optum → Waystar → Provider

Waystar acts as the provider’s front-end clearinghouse. Optum is the downstream trading partner.

Here are the steps to make this process work:

1️⃣ Confirm MDsave’s Optum Payer Setup

As the provider, you need the following from MDsave:

  • Payer ID used in Optum - without this, nothing will route correctly.

    Confirmation that MDsave:

    • Accepts 837s via Optum

    • Generates 835 ERAs via Optum

      ERA delivery method:

    • Direct 835
    • Or via an Optum payer ID + enrollment

2️⃣ Set Up a Cross-Clearinghouse Route in Waystar

You as provider must ask Waystar to route claims to MDsave via Optum.

Waystar must:

  • Map MDsave’s payer ID to Optum as the destination clearinghouse
  • Use Optum’s interconnect (Waystar already has one)

You must tell Waystar Support:

“We submit claims through Waystar, but MDsave only accepts claims via Optum.

We need MDsave configured as a payer routed through Optum so we can submit claims and ERAs can be returned from MDsave to us the same way.”

Waystar will:

  • Create a payer mapping
  • Ensure outbound 837s are sent to Optum
  • Ensure inbound 835s from Optum are delivered to the provider’s Waystar account

3️⃣ Enroll for 835 ERAs

This is the most common failure point, as even if claims go through, ERAs will not flow from the provider without enrollment. Two enrollments typically are needed:

A. Optum ERA Enrollment (Required)

  • Enroll the provider NPI + TIN with:
    • MDsave

    • Via Optum’s ERA enrollment process

      Select:

    • Delivery to Waystar (Optum trading partner)

B. Waystar ERA Configuration

  • Confirm that Waystar is:
    • Receiving 835s from Optum
    • Associating them with the provider’s billing NPI/TIN

If you as the provider skip this step, MDsave will generate ERAs that sit in Optum but never reach you.

4️⃣ Claim Submission Flow

Once configured:

  1. You as provider submitsan 837 to Waystar

    Waystar:

    • Validates the claim

    • Routes it to Optum

      Optum:

    • Forwards the claim to MDsave

      MDsave:

    • Adjudicates the claim

    • Sends payment + 835 to Optum

      Optum:

    • Routes 835 to Waystar

      Waystar:

    • Delivers ERA to the provider (portal, SFTP, or PM system)

5️⃣ Reconciliation and Posting

  • Payments may arrive as:
    • ACH (EFT)

    • Check

      The 835 ERA should match:

    • MDsave remittance details
    • Patient responsibility (often high for MDsave cases)

Waystar will:

  • Auto-post (if enabled)
  • Or allow manual download of the ERA

Common Issues and Why they Occur

Claims are accepted but not ERAs - ERA enrollment is missing or the wrong clearinghouse has been selected.

MDsave says they sent the ERA - It’s sitting in Optum, and hasn’t been forwarded to Waystar.

Waystar can’t find the payer - The MDsave payer ID has not been mapped to Optum in Waystar.

Duplicate payer IDs - MDsave may have one ID for claims and another for ERAs.

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