We download the OCONUS and Foreign Location per diem rates on a monthly bases basis from the following site Per Diem Rate Files (dod.mil) Also you could . The CONUS Location rates effective October 1st of each year are downloaded from the following site Per Diem Rate Files (dod.mil).
You can also reference Per Diem Rates | GSA for more information.
For Meals breakdown we use the following: M&IE Breakdown | GSA
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