# Introducing aggregation preferences for ERA enrollments

> You can now set an aggregation preference – by NPI or TIN – on ERA transaction enrollment requests. The preference tells the payer how you'd like payment information grouped in ERAs.

Published Apr 15, 2026

Product: ERAs & transaction enrollment

You can now set an aggregation preference – NPI or tax ID (TIN) – on ERA [transaction enrollment requests](https://www.stedi.com/docs/healthcare/transaction-enrollment). The preference tells the payer how you’d like them to group payment information in ERAs.

Selecting the right aggregation preference means ERAs arrive grouped the way your billing system expects. Without it, mismatched grouping can require manual reconciliation to match payments to providers or practices.

## What is ERA aggregation?

An Electronic Remittance Advice (ERA) contains payment and adjudication information for one or more claims. Providers use ERAs for payment reconciliation, where they match claims to their payments.

Payers group the information inside an ERA and route ERAs based on one of two identifiers in the related claims:

- Tax identification number (TIN) – A 9-digit tax ID, either a Social Security Number (SSN) or Employer Identification Number (EIN).

- [National Provider Identifier (NPI)](https://www.stedi.com/docs/healthcare/national-provider-identifier) – A 10-digit ID assigned to individual providers and organizations.

### TIN vs. NPI-based aggregation

TINs are sometimes shared across multiple billing providers within the same organization. For example, a clinic may submit claims for several doctors using a single TIN.

NPIs always uniquely identify a single provider entity, either an individual provider or an organization. For example, a doctor employed by multiple clinics may use the same NPI to submit claims across multiple TINs.

Most payers default to TIN-based aggregation. For more background, see [How payers route ERAs](https://www.stedi.com/blog/how-payers-route-eras).

## How aggregation preferences work

Aggregation preferences are a request to the payer, not a guarantee. The payer, not Stedi, controls how ERAs are grouped and routed.

## Checking payer support

Not all payers support both aggregation types. You can check which types a payer supports using the Payers API or the Stedi Payer Network before submitting an enrollment request.

In the [Stedi Payer Network](https://www.stedi.com/healthcare/network):

In [Payers API responses](https://www.stedi.com/docs/healthcare/api-reference/get-search-payers), the [`supportedAggregationPreferences`](https://www.stedi.com/docs/healthcare/api-reference/get-search-payers#response.items.payer.enrollment.transactionEnrollmentProcesses.claimPayment.supportedAggregationPreferences) field lists the supported types. The field is omitted when Stedi has yet to determine a payer's supported aggregation types.

```jsonc
{
  "payer": {
    "enrollment": {
      "transactionEnrollmentProcesses": {
        "claimPayment": {
          "supportedAggregationPreferences": ["NPI", "TIN"], // Payer supports ERA aggregation by NPI and TIN
          ...
        }
      }
    },
    ...
  }
}
```

## Enrollments API

### Setting aggregation preferences

You can now pass the optional [`aggregationPreference`](https://www.stedi.com/docs/healthcare/api-reference/post-enrollment-create-enrollment#body.aggregationPreference) object in [Create Enrollment API](https://www.stedi.com/docs/healthcare/api-reference/post-enrollment-create-enrollment) requests. In almost all cases, the NPI or TIN should belong to the provider being enrolled.

To request NPI-based aggregation, provide an NPI in the [`aggregationPreference.npi`](https://www.stedi.com/docs/healthcare/api-reference/post-enrollment-create-enrollment#body.aggregationPreference) property. For example, in a [Create Enrollment API](https://www.stedi.com/docs/healthcare/api-reference/post-enrollment-create-enrollment) request body:

```jsonc
{
  "transactions": {
    "claimPayment": {
      "enroll": true    // ERA enrollment
    }
  },
  "aggregationPreference": {
    "npi": "1234567890" // Aggregate by the provided NPI
  },
  ...
}
```

To request TIN-based aggregation, use the [`aggregationPreference.taxId`](https://www.stedi.com/docs/healthcare/api-reference/post-enrollment-create-enrollment#body.aggregationPreference) property:

```jsonc
{
  "transactions": {
    "claimPayment": {
      "enroll": true    // ERA enrollment
    }
  },
  "aggregationPreference": {
    "taxId": "999888777" // Aggregate by the provided tax ID (TIN)
  },
  ...
}
```

The `aggregationPreference` object is only supported for ERA transaction enrollments.

### Updating existing enrollments

You can update the [`aggregationPreference`](https://www.stedi.com/docs/healthcare/api-reference/post-enrollment-update-enrollment#body.aggregationPreference) object using an [Update Enrollment API](https://www.stedi.com/docs/healthcare/api-reference/post-enrollment-update-enrollment) request if the enrollment is in the [`DRAFT`](https://www.stedi.com/docs/healthcare/transaction-enrollment#enrollment-statuses) status.

**Payer support for aggregation preference**

Before accepting an enrollment request, Stedi checks whether the payer supports the provided `aggregationPreference`. If not, Stedi rejects the request with an error.

If you omit the `aggregationPreference` field, the payer’s default aggregation method is used.

### Viewing aggregation preferences

The [Retrieve Enrollment API](https://www.stedi.com/docs/healthcare/api-reference/get-enrollment) and [List Enrollment API](https://www.stedi.com/docs/healthcare/api-reference/get-enrollment-list-enrollments) responses now return the submitted [`aggregationPreference`](https://www.stedi.com/docs/healthcare/api-reference/get-enrollment#response.aggregationPreference) object in enrollment records. For example, in a [Retrieve Enrollment API](https://www.stedi.com/docs/healthcare/api-reference/get-enrollment) response:

```jsonc
{
  "id": "db6675c5-7be7-4af9-8c68-a54a336d2911",
  "aggregationPreference": {
    "npi": "1234567890"
  },
  ...
}
```

The object is omitted for enrollments created before this feature was available.

## Stedi portal

You can now use the optional TIN or NPI selectors to indicate an aggregation preference when creating an ERA enrollment request in the Stedi portal. By default, the TIN and NPI values in the selectors belong to the provider being enrolled.

Each ERA enrollment’s details page shows the aggregation preference.

## Availability

[Transaction enrollment](https://www.stedi.com/docs/healthcare/transaction-enrollment) is free on all Stedi plans.

To learn more, check out our [transaction enrollment docs](https://www.stedi.com/docs/healthcare/transaction-enrollment).