Three in five drivers have not read updates to the Highway Code, a survey suggests.
Some 61% of respondents to an AA poll of 13,300 motorists said they had not read changes made in January, designed to provide more protection for vulnerable road users.
New guidance includes things like traffic should give way when pedestrians are crossing or waiting to cross at junctions.
Nine sections of the Highway Code were updated in January, with 50 rules added or amended.
Cyclists are now advised to ride in the centre of lanes on quieter roads, in slower-moving traffic and when approaching junctions.
A hierarchy of road users was also introduced, meaning someone driving has more responsibility to watch out for people cycling, walking or riding a horse, and cyclists have more responsibility to be aware of pedestrians.
The changes were advisory, so non-compliance does not automatically result in a fine.
More than half (52%) of those questioned by the AA had heard about the new rules but not studied them.
One in 10 (10%) drivers aged 18-54 were completely unaware of the updates, compared with 5% of those aged 55 and above.
When asked to identify five correct statements included in the updated Highway Code from a list of 10, the majority of respondents did so correctly.
Tim Rankin, managing director of AA Accident Assist, said: “For many the updated Highway Code formalises safe and sensible roadcraft, however we are concerned that so many still haven’t read the rules.
“While we are pleased that many of the changes can be successfully recalled, we’d like more drivers to know the rules outright so they can keep themselves and others safe.
“It is in everyone’s interest to take every measure that helps avoid collisions and remove confusion from the road, so we urge those that still haven’t read the updated Code to do so as soon as possible.”