We have verified on both TurboTax Online and TurboTax Download and all T4A(OAS) - Old Age Security have Taxable Pension Paid for Box 18. There is no box indicated for Lump Sum Payment.
Please verify that you are in the T4A(OAS) and not the T4A - Pension, Retirement, Annuity, and Other Income where Box 18 is for Lump Sum Payment.
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