@martin-phillips , as a US person ( citizen / GreenCard ), your Social Security Pension is taxable to the same extent as all other SSA recipients i.e. 1/2 Social Security disbursement plus all other income is used to determine whether none or up to 85% of SSA benefits are taxable ( for federal purposes ). So I am not sure where you are reading that your SSA benefits are not taxable. If you are living in Germany ( or for that matter any foreign country ), unless US-that country treaty conditions preclude such ) you as a US person , are taxed as if you are living here in the USA -- USA cannot , for tax purposes , distinguish taxation based on where you live.
Please tell me more about your situation so I can understand the scenario and will help once I hear from you
pk
