A practical guide to completing Box 24A: Dates of Service accurately and consistently.

From our workflow: Dates of Service may be a small entry, but it affects the rest of the claim. We compare it with the source record and then confirm that the surrounding fields tell the same story.

Report the from and to dates for each service line.

An entry for Dates of Service may be the right length and still be the wrong value. The surrounding coverage, provider, and service information has to support it.

General rule: Payer-specific instructions, contracts, program manuals, and current coding guidance can add to or override general form guidance. Verify requirements before submission.

Why payers care about this value

An entry for Dates of Service may be the right length and still be the wrong value. The surrounding coverage, provider, and service information has to support it.

Do not change Dates of Service simply to clear an edit. The value should come from the medical record, service log, and any related authorization, and the correction should be made in the source record when possible.

A reliable way to enter the data

  1. Identify the person, organization, date, code, or identifier the field is asking for.
  2. Locate the source document: insurance card, eligibility response, clinical note, authorization, provider enrollment record, fee schedule, or payer remittance.
  3. Enter the value using the form’s structure and the payer’s required format.
  4. Compare it with related fields and service lines for consistency.
  5. Save evidence of the source and the final submitted claim.

Where errors tend to appear

  • Using claim creation date.
  • Combining nonconsecutive dates.
  • Billing outside the authorization range.

We do not treat the last paid claim as the source for Dates of Service. It may contain information that was valid then and is no longer valid now.

Before the claim leaves your office

  • Match the clinical record.
  • Use valid date ranges.
  • Separate services when required.
  • Check coverage and authorization dates.
  • Compare the completed claim with the clinical and billing record.
  • Confirm the receiving address or electronic route.
  • Keep a secure copy and proof of submission.

Where software helps—and where it does not

A dependable program can reuse stable records and flag inconsistent entries for Dates of Service. It should not silently guess at information that is absent or uncertain.

Apply this in software: For a workflow that keeps claim data reusable and reviewable, see the CMS-1500 paper and electronic filing options. Software can enforce format and consistency, but the source record and payer instructions still control the claim.
Privacy reminder: Use fictional data for training and printer tests. Claims contain protected information and should be stored, transmitted, printed, and destroyed through approved secure processes.

Written and reviewed by

1500Software Development Team

Covers the software, printing, validation, export, and troubleshooting steps described on this page.

1500Software Claims Review Team

Reviews field placement, provider roles, source records, and practical correction steps.

Reviewed July 26, 2026. Always follow the receiving payer’s current instructions and companion guide.

Source material

These are the national sources we use as a starting point. The receiving payer may add more specific instructions.