Our 1998 306 1.4l has a 72,000 mile Peugeot recommended timing belt
replacement interval.  At 12,000 miles per year, this works out at every
6 years.

Most people recommend it gets replaced much earlier than 72,000.  Haynes
recommends 36,000.

I've also heard that if on a low mileage car, it's worth replacing it
around 5 years, even if the mileage limit isn't hit.

Our Peugeot dealer quoted £99 to replace our timing belt (up from £75 or
so a few years ago).  But I believe this to just be the belt - not any
of the pumps/tensioners etc running off that belt, which many people
recommend as often these are the causes of belt failure when they jam etc.

D

For your car it is 80,000 miles or 5 years, so it is due on time
basis. I would suggest getting a cambelt kit fitted which includes the
static roller and the tensioner roller. Also renew the auxilliary
belt. If there are signs of leakage from the water pump renew that
too. Labour time is around 3.5 hours for the belt and 4.5 if the water
pump needs doing. In this case you will need antifreeze. Which by the
way should also be changed every 5 years!

Take a look in your owner's manual - it lists the exact service schedule, with a
breakdown of what needs doing when.
My 2001 3.0 V6 Coupe states the cambelt needs doing every 4 services / 80,000
miles / 8 years (although leaving it for 8 years is probably a bad idea - I plan
to have mine changed next year).