If you made a mistake on your original return, you can amend it to correct the error. To do so:
- Complete a new return for the affected period. You must include both original and corrected premiums on the form (not just the new information).
- Check the “Amended Return” box at the top of the form.
- Include a cover letter that explains what was changed from your original filing and why you changed it.
You must file your amended return within 3 1/2 years from the due date of the original return. All amended returns are subject to audit.
Make sure to keep all supporting documentation from your original and/or amended return. That documentation must be available upon the department's request.