The amount of medical service fees you must pay for out of pocket in a calendar year before your insurance plan begins to contribute to the cost of medical services. For instance, if your deductible is $2,000, you must pay the full amount of billed medical service fees until you have spent $2,000. Once you have spent $2,000, your insurance plan will then begin to pay for a percentage of your medical fees or all of your medical fees depending on your policy.