Traditionally commercial transports don't have a service life. They used a different philosophy, first "fail-safe" which instead of a fixed life says that loads can be carried on secondary paths until the primary failure is found during routine inspection (or earlier) and fixed. This has been superseded by "damage tolerance", which uses an inspection program to find detectable faults before failure.
The military typically used a "life limited" approach, which is that nothing major will fail for a given period, say 10,000 hours of flight time. When military aircraft near that limit and require further service, a "service life extension program" may be carried out to extend the life by analysis, inspection or modification or some combination thereof.
Airbus may use a service life; I don't know.
The FAA is nearing rulemaking that essentially will put a life limit on aircraft. The concern is "widespread fatigue damage" that as I understand holds that after so long multiple element/multiple site fatigue damage may exist and have the potential to propogate so fast that practical inspection intervals can't catch them. This is a really controversial issue. The verbage used is "limit of validity" in which the OEM basically says "based on our testing, analysis, and service information we are confident the existing inspection program will remain valid until a certain number of hours/cycles and beyond that...we don't know at the moment". It is not exactly a life-limit but economically it probably will be. The limit is quite large for most aircraft. DC's are tough and the LOV proposed is 60,000 cycles / 150,000 hours for DC10's. I don't think any DC10 at the moment has reached the proposed LOV and later production planes are relatively far from it.
