I have a 401A plan with STRS, contributing for the past 10 years. Prior to that I paid into social security. My question is will having the 401A plan affect my social security benefits?
Receiving distributions from a 401(a) plan certainly could affect your Social Security benefits. Social Security's Windfall Elimination Provision (WEP) can cause a person's Social Security retirement or disability benefit rate to be calculated using a less generous computation formula than the normal formula (https://www.ssa.gov/pubs/EN-05-10045.pdf) if they also receive a pension or distributions from a retirement fund based on their earnings that were exempt from Social Security taxes.
Whether or not your 401(a) will cause your Social Security benefits to be reduced depends on a number of different factors, though. Our software (https://maximizemysocialsecurity.com/purchase) is fully programmed to handle computations involving the WEP provision, so you may want to strongly consider using the software to do your Social Security planning.