Updated 24 March 2026
Dartford Crossing Alternatives: Free Routes
Three free alternatives exist. All involve going through London, which adds time. Here is an honest comparison.
| Route | Cost | Extra Time vs Dartford | Height Limit |
|---|---|---|---|
| Dartford Crossing (A282) | £2.50 | Baseline | None (bridge is 57m clearance) |
| Blackwall Tunnel (A102) | Free | +30-60 mins | 4.0m |
| Rotherhithe Tunnel (A101) | Free | +40-75 mins | 3.5m |
| Woolwich Ferry | Free | +45-90 mins | None (open deck) |
| Silvertown Tunnel (2025+) | TBC (likely tolled) | +20-40 mins | TBC |
Blackwall Tunnel (Best Free Option)
Route: A102 through Greenwich. Two bores: northbound is newer and larger, southbound is older and has the 4m height restriction.
Adds: 30-60 minutes depending on traffic. During rush hour, the tunnel itself queues for 20-40 minutes.
Best for: Journeys to/from south London, Kent coast, or when Dartford is closed.
Avoid if: You have a tall vehicle (over 4m), or it is rush hour (the tunnel congestion can be worse than Dartford).
Woolwich Ferry (Best for Tall Vehicles)
Route: Free vehicle ferry across the Thames at Woolwich. Carries cars, vans, and HGVs with no height restriction.
Adds: 45-90 minutes including waiting time. The ferry runs every 10-15 minutes but queues can be long.
Hours: Monday-Saturday 6am-8pm, Sunday 11:30am-7:30pm. Closed outside these hours.
Best for: HGVs and tall vehicles that cannot use the tunnels, or when both tunnels are closed.
Is It Worth Avoiding the Charge?
At £2.50, the Dartford Crossing saves 30-90 minutes vs free alternatives. Your time would need to be worth less than £1.70-5.00/hour for the detour to make sense financially. For most people, paying the £2.50 is the better deal.
The exception: if you cross 5+ times per week, the savings add up. At £2.50 x 10 crossings (return) per week = £25/week = £1,300/year. A pre-pay account reduces this to £1,040. But taking alternatives 10 times a week would add 5-15 hours of driving time.
Verdict: The free alternatives only make sense if Dartford is closed, you have a height-restricted vehicle, or you genuinely enjoy sitting in London traffic. For everyone else, £2.50 (or £2.00 pre-pay) is the obvious choice.
See all Dartford Crossing costs
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