16/07/2026
The M5 southbound, A303, and A30 into Cornwall are now at their annual peak volume and will remain there through August. For anyone travelling to Devon, Cornwall, or Somerset this summer, here is the practical picture.
The M5 southbound carries its heaviest pressure on Friday afternoons from junction 20 southward, with consistent congestion around Taunton and Exeter. The A303 is reliable until the Stonehenge section, which backs up on any busy Friday regardless of the time you leave. The A30 into Cornwall becomes the bottleneck once you are through Exeter, particularly around the Bodmin area.
The windows that can work: before 10am on Saturday, or arriving after 7pm on Friday. Travelling on a Thursday rather than a Friday makes a significant difference on both routes. If you are travelling with a caravan or towing anything, the same principles apply with less flexibility in overtaking opportunities.
Keep AutoAid in mind for UK breakdown reassurance this summer.