According to the IRS, "Under income tax treaties with Canada, social security benefits paid by those countries to U.S. residents are treated for U.S. income tax purposes as if they were paid under the social security legislation of the United States.”

Enter your Old Age Security pension in Wages & Income / Retirement Plans and Social Security / Social Security (SSA-1099, RRB-1099)

Refer to How do I enter my Canadian Pension Plan (CPP) or Old Age Security (OAS) benefits?

Your answer is for those residing in the US it is added to SSA.  We are US citizens permanently living in Italy.

We have SSA plus foreign government social security consisting of CPP plus OAS plus UK BSP.

Where should these be entered as we are citizens but not resident in the US?