To encourage United States military personnel to reenlist in the Army, Navy, Marine Corps or Air Force, the military offers a reenlistment bonus. Bonus amounts vary based on such criteria as your job, your current pay and the number of years you're reenlisting. To calculate your reenlistment bonus, follow these steps.

Determine your monthly base pay. If you don't already know it, find it on the military pay chart.

Find your reenlistment zone among the three zones. Zone A covers those who have already served 21 months to six years; Zone B covers six to ten years; and Zone C falls between ten to 14 years.

Figure out your SRB or specific bonus multiplier, based on your MOS, your job classification, and your reenlistment zone. You can find all the figures you need through your military manuals and resources.

Take your monthly base pay and multiply it by the SRB, or bonus multiplier.

Multiply that figure by the number of years you plan to enlist. The result gives you your reenlistment bonus total amount. You receive half when you reenlist, and the military divides the other half into your annual pay.