M5 data reveals Devon’s ‘Friday trap’—and it could cost drivers 50 minutes

Motorists heading into Devon are being caught in a predictable—and costly—traffic pattern, with new data revealing a recurring “Friday trap” on the M5 that can add up to 50 minutes to journeys.

Analysis by transport analytics firm INRIX highlights a consistent bottleneck on the southbound stretch between Junctions 27 and 31, with Friday afternoons emerging as the worst time to travel—especially during the busy August holiday period.

According to the data, delays during these peak times can surge well beyond normal conditions, with summer getaway traffic identified as the main culprit. The worst congestion tends to cluster around school holidays, bank holiday weekends, and Christmas travel periods.

The takeaway for drivers is simple: avoid southbound M5 journeys into Devon on Friday afternoons if possible—particularly in August.

Despite the findings, National Highways maintains that overall congestion levels in the region have remained stable in recent years. Traffic volumes on the M5’s busiest days—typically Fridays in summer—hover between 60,000 and 70,000 vehicles in each direction.

The agency also notes that delays can vary significantly depending on factors such as weather, incidents, and roadworks, and says measures are in place to keep traffic moving, including additional recovery vehicles during peak periods.

Still, the data paints a clear picture: if you’re heading to the South West for a summer getaway, timing your journey could make the difference between a smooth drive and nearly an extra hour on the road.