Dear Larry - my husband and I have been living and working in Japan for a number of years. We qualify for SS benefits based on our earlier employment in the US. My question is - we are now looking towards retirement but still in Japan and working and our salaries here are much higher here - does it make sense to pay into SS in these last few years of work to increase our SS benefits - the software you have seems to indicate this is the case but wanted to be certain. Just FYI - working outside of the country we did not pay SS but, of course, pay all other US taxes and Japan taxes. Thanks!
You aren't allowed to voluntarily pay Social Security taxes in order to qualify for benefits or boost your benefit rate. Social Security taxes are only collected on wages paid by employers subject to U.S. Social Security taxes, and on net-earnings from self-employment which are subject to U.S. self-employment taxes. I don't have enough information about your current employment to know for sure, but I doubt if your work in Japan would be subject to U.S. Social Security taxes.