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GSA Per Diem Long-Term Travel: The Reduced Rate After 30 Days

A 45-day TDY to the same city sounds like 45 days of full per diem. It often is not. Here is where the 30-day line comes from, who decides your reduced rate, why DoD travelers live under a different schedule, and the worked math of a 45-day trip at full vs reduced rates.

The rule most travelers half-remember is real: under the Federal Travel Regulation, an authorizing official may set a per diem rate below the published rate for the locality when lodging or meal costs will run lower than the established rate. The FTR names two situations explicitly. One is an extended training assignment where the training institution or nearby facilities offer reduced rates. The other is extended or long-term TDY, meaning more than 30 days, where the employee can get lower-cost lodging on a weekly or monthly basis. A 45-day assignment with a monthly extended-stay rate fits the second case exactly.

The part people get wrong: it is not automatic

Unlike the DoD schedule, which cuts the rate by formula, the GSA side is discretionary. The authorizing official has to make the call before the trip, based on actual circumstances at the locality, and the reduced rate has to appear in the travel authorization. No reduced rate on the authorization means no reduced rate on the voucher. If you show up to a 45-day TDY and learn mid-trip that the agency wants to pay you less, that conversation should have happened before you booked. Get the rate in writing on the authorization, and if it is not there, ask.

Agencies also close the obvious loophole. Policy prohibits splitting one long TDY into multiple short authorizations to dodge the reduced rate or the tax rules. A traveler at the same location doing the same job for 30 or more consecutive calendar days falls under the reduced-rate rules regardless of how the paperwork is sliced.

The DoD schedule, for comparison

DoD civilians and service members live under a different, automatic schedule. For TDY of 31 to 180 days in one location, DoD pays 75% of the location's per diem, lodging plus meals and incidentals. Beyond 180 days it drops to 55%, and stays past 180 days need senior-level approval. The logic is the travel industry's: past 30 days counts as an extended stay, and extended-stay housing costs less per day than transient hotels. If you are a GSA-agency traveler, do not apply the DoD percentages to your own voucher. They are a different rulebook.

The worked math: 45 days at full vs reduced

Take the FY2027 standard rates: $113 lodging and $68 meals and incidentals, $181 a day. At the full rate, 45 days comes to $8,145. Now suppose the authorizing official finds a monthly extended-stay at $2,400 a month, about $80 a night, and authorizes lodging at $80 while keeping M&IE at the full $68. The reduced math is $80 plus $68, times 45 days: $6,660. The traveler gives up $1,485 and gains a kitchen, a washer, and a monthly rate that cannot spike mid-trip.

Full per diemReduced per diem
Lodging per night$113$80
M&IE per day$68$68
Daily total$181$148
45-day total$8,145$6,660
The negotiation angle: if you are the traveler and a reduced rate is on the table, the extended-stay kitchen is your leverage for keeping M&IE whole. The FTR lets the official reduce lodging, meals, or both. A kitchen that cuts your restaurant spending is the argument for a lodging-only reduction. Agencies sometimes reduce the whole package by default, and a specific ask backed by the actual lodging quote gets better results than a general complaint.

So the answer to the search that brought you here: there is no single GSA reduced rate after 30 days. There is an official, a locality, an authorization, and a number they agree on before you travel. DoD travelers get the fixed 75% and 55% schedule. Everyone else gets a conversation. Have it before you book, get it in the authorization, and price the extended-stay yourself so you walk in with the number.

Rates referenced are FY2027 CONUS figures. Agency policies vary; confirm the reduced-rate rules with your authorizing official before travel.

Frequently asked questions

Does GSA automatically reduce per diem after 30 days of travel?

No. Under the Federal Travel Regulation, the authorizing official may authorize a reduced per diem rate for TDY longer than 30 days when lower-cost lodging is available. It is discretionary, must be approved before travel, and written into the travel authorization. The automatic 75% and 55% schedule is a separate DoD policy.

What is the DoD reduced per diem schedule for long-term TDY?

DoD policy pays 75% of the location per diem for TDY of 31 to 180 days and 55% for TDY longer than 180 days. Stays past 180 days need senior-level approval. This schedule does not apply to civilian agencies under GSA's Federal Travel Regulation.

Can my agency split a long TDY into shorter authorizations to avoid the reduced rate?

No. Policy explicitly prohibits using multiple travel authorizations for shorter periods to circumvent a reduced per diem rate or applicable tax rules. A traveler at the same location doing the same job for 30 or more consecutive calendar days falls under the reduced-rate rules.

Is long-term per diem taxable?

Per diem for travel generally is not taxable, but assignments expected to last more than a year can change the tax treatment under the IRS one-year rule. If your TDY approaches that line, confirm the treatment with your agency's travel office. This is general information, not tax advice.

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Related reading: When Your Hotel Costs More Than the GSA Per Diem · The 75 Percent Rule for First and Last Travel Days · Can Federal Employees Keep Unused Per Diem Money? · FY2027 GSA Per Diem Rates: What Changed