After working in the private sector and having “substantial earnings” and Social Security contributions for 25 consecutive years, I left the workforce in 2012 at age 45, took two years off to get a graduate degree, and then became a public elementary school teacher in Massachusetts. I intend to work exclusively as a public school teacher for at least 15 years (with no outside covered work during this time, thus no Social Security contributions) and expect to collect a modest pension from this brief teaching career starting at about age 63.
I have assumed that I will be eligible at 67 (or earlier) for a Social Security benefit based on my 25 years of private sector earnings, though I understand that benefit will be reduced to some degree by the Windfall Elimination Provision triggered by the collection of my teacher’s public sector pension. However, I was warned by an acquaintance that my expected Social Security benefit will be in jeopardy if, when I apply for that benefit at 67, I have not made any contributions into the system for the 11 years prior to the application. This would be the case for me, since at age 67 I would not have made any Social Security contributions for at least 20 years, at least according to my current plan. Would my Social Security benefit indeed be affected under this scenario? If so, is there anything I can do to avoid it?
Social Security retirement benefits are calculated based on the best 35 years of a person's inflation adjusted earnings on which Social Security taxes were paid. If you only have covered earnings in 25 years, 10 years of zero earnings will be averaged into your benefit calculation, which will obviously drag down the average and the resulting monthly benefit payable. On top of that, as you're already aware, the WEP provision (https://www.ssa.gov/pubs/EN-05-10045.pdf) will likely reduce your benefit by an additional amount.
The only way to reduce the impact of these provisions would be to resume paying Social Security taxes, and the only way to do that is to work in Social Security covered employment, or to have net earnings from self-employment. Whether or not the resulting increase would be worth the additional work and taxes you'd pay is the question. You may wish to run the maximization software available on this website in order to get a better idea of your options.