Use of the Signs

Signage for With-flow Bus Lanes

Chapter 3 of the Traffic Signs Manual sets out how to use regulatory signs, including those for bus lanes. The figure below is taken from the current (2019) edition:

The accompanying text explains:

9.3.3.  The start of the lane is marked with a broken line to diagram 1010 (S11-4-10), the same width as the 1049A marking [250 or 300mm], and normally laid at a taper no sharper than 1:10. There may be situations where it is not practicable to provide a taper of 1:10 and a sharper taper is necessary. In such circumstances, care should be taken to ensure that traffic is directed away from the start of the bus lane in a safe manner… The bus lane should not start in such a position that the marking to diagram 1010 would extend across a side road junction. Deflection arrows to diagram 1014 (S11-4-14, see Chapter 5) 4.5 m in length should be placed 15 m and 30 m upstream of the start of any taper where general traffic is required to deflect but certain vehicles are not…

Apart from the changes to diagram numbers, the only change from 40 years before is that the deflection arrows are now to be placed 15m and 30m before the start of the taper rather than before the start of the bus lane.

Signage for Contraflow Bus Lanes

The text explains:

9.4.2. A contraflow bus lane is effectively a one‑way road with a bus lane (or bus and cycle lane) running in the opposite direction. 

The typical layout is:

Signage for Bus Gates 

Beneath the blue roundel with a bus and a cycle an “only” plate was mandated. This must be seen in the context of widespread confusion about the only sign at that date which showed a white vehicle in a blue roundel: a cycle.

The confusion arose because there were two signs with a white cycle on a blue background:

• the roundel (diagram 625, superseded in TSRGD 1994 by diagram 955);

• the rectangular sign (diagram 815, superseded in TSRGD 1994 by diagram 967)

Both had been used on cycle tracks which were separate from the main carriageway. Under TSRGD 1975 the roundel meant that cyclists were obliged to use the cycle track, while the rectangular sign meant that cyclists could use it.

TSRGD 1981 removed the element of compulsion from the roundel. Now it meant that only cyclists could use the track with the sign, but they weren’t obliged to. The meaning of the rectangular sign changed to “route recommended for pedal cyclists” and it was used with cycle lanes which were then being created on the main  carriageway.

With this confusion about what a white symbol on a blue background meant, it was understandable that the Department mandated the “Only” plate beneath a white bus and a cycle on a blue roundel. The sign meant “Buses and cycles only” rather than “Route recommended for buses and cycles (but other vehicles can also use it)”.

When the blue roundels showing a bus were introduced in TSRGD 1994, the standard size for a 30mph zone was 600mm diameter, the same as most round signs. In TSRGD 2002 it was changed to 750mm and this was confirmed in the 2008 edition of Chapter 3 of the Traffic Signs Manual. This advised that the 600mm sign was only to be used for special environmental reasons or where physical constraints applied. But the damage had been done: to this day, most blue roundels are 600mm diameter, which makes them hard to read from a distance.

At TSRGD 2016 the Department did an about-turn on the “Only” plate. Not only was it no longer mandated, its use was prohibited on new signs. Unfortunately, nobody seems to have told those responsible for The Highway Code. It continues (as at the 2025 edition) to show the blue roundel with “Only” beneath it. 

One change, which may have precipitated the removal of the "Only" plate, was that bus gates now joined with-flow bus lanes in being able to be part-time. This required a plate below the blue roundel to specify the days and hours of operation. 

Another stimulus was pressure from local authorities to add extra types of vehicle or to qualify those which were permitted. Nottingham and Reading restrict the taxis which are permitted through bus gates to wheelchair-accessible ones. This requires a blue roundel showing a bus and a cycle with the plate "and wheelchair accessible taxi only". 

Written 16th November 2025; last updated 24th February 2026