How busy does the M25 get in rush hour between junction 5 and junction 15?

I am traveling from Folkestone to Bristol on Friday morning. The route requires going on the M25 clockwise from junction 5 (M20) to junction 15 (M4). Can anyone advise me of the likely travel time this section of my trip might take and what are the worst rush hour times for that section of road? I have to be at Bristol by 12.30 and cannot get on the M25 until about 8 or 9am.

Asked on 4 August 2010 by SALT3178

Answered by David Ross
Rush hour times for the M25 are exactly that - at rush hour, so you can expect it to be busy from 7am until 10am and then again from 5pm until around 7pm. The section of the M25 you are covering gets busy due to the M23, A3 and M3 junctions. We'd allow two hours for that section of the M25 at that time in the morning, as it's unpredictable in terms of traffic.
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