My drivers seat belt has frayed at the buckle about 1/4" of the 'across' thread seems to have suddenly gone. How much is it  likely to cost to replace the belt? Just so I am primed for the dealers quotes and any others I get.

Disappointed as the car has done less than 80000 miles in 6 years .

£114 - see here:

http://www.skodaparts.com/product/octavia-seat-belt-2004-2013-31868

I had to replace a seat belt due to it fraying, the plastic trim that is on the pillar actually had a groove in it that the seat belt had made, this led to the belt fraying.

I should have renewed the trim, as the belt is fraying again.

Thanks for that. Will try to get it done at MOT/service time as I can not face two trips to the main dealer.

Mine has frayed exactly at the buckle when it is sitting on me.

Got car booked in and the seatbelt replacement is ~£190 all in. 'We don't see many like that.'

Mines frayed as well, I'm going to source a 2nd hand belt from eBay as they go for around £35.

Bear in mind that seatbelts contain the pretensioner and are explosive, take the same precautions that you would do with an airbag when handling them.