The amount you must pay for healthcare services before your insurance plan begins making payments on claims.
There are typically two types of family deductibles: per person or aggregate. Per person deductibles are where when one covered person reaches the deductible, the insurance plan will begin to pay claims for that person. Many family per person deductible plans will have a two person maximum, so that after two people have each satisfied their deductible, the third person will not have to reach the deductible before claims are paid
Aggregate deductibles are often found in HSA-eligible plans. For aggregate deductibles no claims are paid by the insurance company until the combined payments made by the family satisfy the deductible.
Many plans have different provisions, so please see the details of the insurance plan you are considering.