Everything you need to know about the Blackwall Tunnel

If you’ve ever listened to traffic reports in and around London, you’ll know just how often the Blackwall Tunnel seems to get mentioned.

But what is the Blackwall Tunnel? And what do you need to know if you’re going to be using it on your next road trip?

To help put any concerns you might have to rest, here’s our guide to everything you need to know about the Blackwall Tunnel.

With recent changes, drivers in the capital need to be aware of what is to come.

What is the Blackwall Tunnel?

The Blackwall Tunnel is actually two separate tunnels that travel beneath the Thames in East London — one tunnel for southbound traffic and the other for northbound traffic.

The original Blackwall Tunnel was officially opened by the then Prince of Wales on 22 May 1897 as a £1.4m project aimed at improving trade and commerce in and around London’s East End and the nearby docklands.  

Originally used by horse-drawn carts, cyclists, and pedestrians, as vehicular traffic grew so did congestion in the tunnel, forcing authorities to build a second Blackwall Tunnel, which opened to the public in 1967.

The original tunnel now supports northbound traffic, while the newer tunnel acts as a southbound route, with all non-motorised traffic now banned from using the tunnels in favour of car traffic.  

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Where is the Blackwall Tunnel?

The Blackwall Tunnel travels underneath the River Thames in east London, connecting Poplar and the Essex-bound A12 in the north to North Greenwich and the Kent-bound A2 in the south.

The Tunnel itself forms part of the A102, with the southbound tunnel passing underneath the O2 — formerly known as the Millennium Dome — as it travels below the river slightly downstream from its northbound neighbour.

Despite various stalled plans to build another Thames crossing, the Blackwall Tunnel remains one of the most easterly road crossing on the river, with only the Dartford Crossing (toll) and the Woolwich Ferry further east.

Is there a toll for the Blackwall Tunnel?

From April 7th 2025, the prices to travel through the Blackwall and Silverton Tunnels have been updated.

Here is what you can expect to pay to use the tunnel:

Blackwall Tunnel traffic

Unsurprisingly, the Blackwall Tunnel is busiest during the morning and evening rush hours, however Transport for London (TfL) data shows that there are differences between the two tunnels.

The northbound tunnel is busiest during the morning rush hour— between 06:30 and 08:30, while the southbound tunnel sees most traffic in the evening rush hour, from 16:00 to 18:00. Drivers can be held up for 20 minutes or more during busy times.

Is the Blackwall Tunnel open?

The tunnel is open 24 hours a day, unless the authorities have concerns over driver safety in the event of a fire, crash, or an unauthorised road user using the tunnels.

However, the tunnels are regularly closed for routine maintenance works, with these works usually happening at quieter times such as overnight or over the weekend.

If you’re intending to use the Blackwall Tunnel but it’s closed, you’ll need to find an alternative route to cross the Thames so check the RAC Route Planner for the latest up-to-date traffic news to rearrange your journey.

What’s the closest alternative Thames crossing?

While you might think of the Thames being criss-crossed by bridges as it passes through London, there are actually very few river crossings in east London which is why the Blackwall Tunnel is such an important route.

The nearest vehicular river crossings to the Blackwall Tunnel are the Rotherhithe Tunnel two miles to the west and the Woolwich Ferry two miles to the east, although the ferry does not run overnight.

Further afield, Tower Bridge is located three miles to the west while the Dartford Crossing is 16 miles to the east of the Blackwall Tunnel, although there is a toll to use to use the latter.

Is there a height restriction for the Blackwall Tunnel?

The Blackwall Tunnel has a height restriction of 4m (13'0”) northbound, 4.7m (15'6”) southbound, so ensure that your vehicle can safely navigate the tunnel before making your journey.

It is an offence to ignore a height restriction sign, and you could be hit with a Fixed Penalty Notice of a £60 fine and three points on your licence if you’re caught ignoring the signs.

What’s the speed limit in the Blackwall Tunnel?

The speed limit in the Blackwall Tunnel is always 30mph or 48km/h.

Why is the Blackwall Tunnel curved?

If you’ve ever driven through the Blackwall Tunnel, you’ll notice that the tunnel has several sharp bends so it could align with Northumberland Wharf to the north and Ordnance Wharf to the south, as well as avoiding a nearby sewer.

Another reason for the curved tunnel is due to the fact that the main mode of transport when it opened was horse and cart, so the tunnel had to be curved to avoid the horses seeing daylight at the end of the tunnel and bolting towards it.

Will there be a third Blackwall Tunnel?

Due to congestion and the need for occasional closures for routine maintenance, a third bore of the tunnel was proposed in 1989 by Cecil Parkinson – the then Transport Secretary.

The third tunnel never made it off the drawing board due to logistical issues, but the idea of a new Thames crossing in east London has been discussed for many years, with plans approved in May 2018 for the Silvertown Tunnel.

The new link, would connect the Royal Docks north of the river to North Greenwich in the south, linking up near the southern entrance of the Blackwall Tunnel.

It opened on April 7th 2025.

Blackwall and Silvertown Tunnel in 2025

Drivers using the Blackwall Tunnel and the new Silvertown Tunnel will be required to pay a toll, with car journeys costing up to £4 each way.

This charge is being introduced on the same day the new Silvertown Tunnel opened (7th April 2025), which will connect east London to southeast London (near the 02 Arena).

For car drivers, a round-trip during peak hours will cost £8, while large vans will face a charge of up to £13.

The Silvertown Tunnel is designed to ease congestion around the Blackwall Tunnel, with Transport for London (TfL) claiming it will reduce journey times by up to 20 minutes.

TfL explains that the Blackwall Tunnel was not built to handle the current volume of traffic, resulting in more frequent incidents that cause long delays and negatively impact air quality.

In addition to private vehicles, around 21 buses will pass through the new tunnel every hour from 7am to 7pm, Monday to Friday, offering new routes for passengers.

A dedicated shuttle service will also transport cyclists and their bikes across the river. Both tunnels will operate 24 hours a day, seven days a week (including bank holiday).

Tolls must be paid by phone or online, with the easiest payment method being Auto Pay, which links payment cards to an account for automatic payments.

Failure to pay the toll will result in a £180 penalty charge, which can be reduced to £90 if paid within 14 days.

What is the Silvertown Tunnel?

The Silvertown Tunnel opened on April 7th 2025, connecting Silvertown in east London with the Greenwich Peninsula. It will alleviate congestion at the Blackwall Tunnel, improve journey times during peak hours, and provide an alternative route when the Blackwall Tunnel is closed for maintenance or repairs.

The new tunnel will support faster cross-river travel during busy periods (06:00-10:00 northbound and 16:00-19:00 southbound, Monday to Friday) between the north and south of the River Thames in east London, helping to reduce traffic in the Blackwall Tunnel area.

A new dedicated shuttle service will allow cyclists to secure their bikes and travel through the Silvertown Tunnel on a shuttle bus, ensuring a safe crossing with clear signage to cycleways at both riverbank stops.

The service will have stops at Seagull Lane (north) and Millennium Way (south), with five buses running per hour from 06:30 to 21:30 every day (except Christmas Day). This service will be free for cyclists for at least 12 months. All buses will be zero-emission.