You do not need to file form 8606 every tax year,
Form 8606 is only necessary when you have the following in the tax year:
- Nondeductible contributions you made to traditional IRAs.
- Distributions from traditional, SEP, or SIMPLE IRAs, if you have ever made nondeductible contributions to traditional IRAs.
- Conversions from traditional, SEP, or SIMPLE IRAs to Roth IRAs.
- Distributions from Roth IRAs.
Please read this IRS document for more information.