I worked in Amsterdam this year for six months and received a flat $65 a day per diem. We had an apartment that we paid for, but got reimbursed. Travel was paid for by the company, so that was not an issue. My question is, since I was given the $65/day, and the M&IE for Amsterdam is $182, can I write off the difference? If so, what form would I use?
I have also been working in Florida the rest of the time and have been getting $40 a day. The M&IE per diem rate is $51/day. Any chance of writing off that difference?
Thanks!

If you deduct the per diem expenses ($182) using the GSA per diem rate (using Form 2106 and doing the deduction as a Miscellaneous DEDUCTION on Schedule A), then you have to declare the $65 daily reimbursement, plus the other reimbusements, as income on the Form 2106. You CANNOT deduct just the difference; the payments MUST be accounted for.

Same applies for Florida.