You’re covered by an employer retirement plan for a tax year if your employer (or your spouse’s employer) has a:

• ...
   
• IRA-based plan (SEP, SARSEP or SIMPLE IRA plan) and you had an amount contributed to your IRA for the plan year that ends with or within the tax year

https://www.irs.gov/retirement-plans/are-you-covered-by-an-employers-retirement-plan#:~:text=You're%...