Post Allowance

 The amount of P A an employee receives is determined by the post of assignment, the
post classification levels, salary band, and family size.

Yes, if an employee transfers to another overseas duty location, he/she needs to submit a new SF 1190 and the rates will be adjusted to the new duty location.

 No, PA is not taxable income.

PA is a cost-of -living allowance granted to an employee officially stationed at a post in a foreign area where the cost of living, exclusive of quarters costs, is substantially higher than in Washington, D.C. Allowance payments are based on family size and salary levels.
To initiate payment of PA, you must submit a completed SF-1190, Foreign Allowances Application, Grant, and Report, through the DoDEA Allowance Processing System (DAPS). Employees also should submit a SF 1190 when there is change in the number of dependents, a change in work schedule from full-time to part-time or intermittent, when Temporary Quarters Subsistence Allowance is initiated, or when separating from Federal service.

Employees can find the P A rates in the post classification tables in Section 229 of the
DSSR at the above web address.

The regulation authorizing PA is the Department of State Standardized Regulations (DSSR), section 220. You may read more about post allowance at the following web address:

No. Employees must be on a full-time or full-time seasonal work schedule to be eligible. Additionally, PA must be authorized by the State Department for the employee's duty station.