If you received a lump sum payment during 2017 that was for
2017, then it would be included in the total amount reported for 2017. If you received a lump sum payment during
2017 that was for a prior year or years, then that information is entered into
your tax return along with some information from your prior year returns to
determine if any of the lump sum is taxable.
Please take a look at the TurboTax article below for more
information about Social Security lump sum payments.
https://ttlc.intuit.com/replies/4767454
