Well of course we recommend giving to MAAF:
Atheists in Foxholes:
Military Association of Atheists & Freethinkers
CFC # 80918
The Combined Federal Campaign is a list of charities disseminated by the US Government to all government employees, basically like the United Way. Federal employees can easily select from among these vetted and approved charities for their personal giving programs. MAAF is currently listed, and MAAF also accepts donations directly – one-time donations or automatic, recurring donations just like CFC.
You should also consider other CFC charities. MAAF has reviewed programs to identify the charities with the best fit to MAAF goals of supporting nontheists in the military and promoting interfaith toleration. Many other secular and humanist organizations are also listed.
See a full review, last conducted in 2012.