Motorists could be spending hundreds of pounds more because of new rules that take effect today.

Car taxes, penalties and passenger regulations are all part of the new laws that came into place from March 1.

Drivers who use their mobile phones at the wheel will be hit with stronger penalties.

The new fixed penalty notice will double from £100 to £200 and from three points to six points on your licence.

New safety rules for child car seat manufacturers have also been introduced, and certain models have been withdrawn from the market entirely, reports the Mirror .

Here's are breakdown of the major changes for drivers that take affect from March 1.

1. New penalties for mobile phone users

News laws on using your phone when driving come in today

Since December 2013 it has been illegal to use a hand-held device while driving or while stopped with the engine on.

From today drivers will be hit with stronger penalties for using a handheld mobile at the wheel.

The new fixed penalty notice will double from £100 to £200 and from three points to six points on your licence.

You could even face prosecution if police do not think the fine is enough of a penalty, especially if you are involved in a crash.

The new rules are especially strict on new drivers, with anyone caught who has been driving less than two years likely to have their licence taken off them.

Bus drivers and good vehicle dries could face fines from £1,000 and £2,500 if taken to court.

It's not just mobile phones

The same rules apply to all electronic devices which can be connected to the internet - including iPods, tablets, and some digital cameras.

If you want to use a device, look for a suitable place to stop, and make sure your engine is switched off.

If you are supervising a learner driver, you cannot use a handheld phone or similar device, as you are in charge of the vehicle.

Can I still use my mobile phone as a sat nav?

The law says you can use your mobile phone as a sat nav - but only if you programme it before you start the car.

It must be in a holder out of the 45-degree angle of the driver's view. You can't re-programme or touch it while in motion, the same rules apply for any sat nav.

2. Child car seat rules - some models are now banned

Children must normally use a child car seat until they are aged 12 or 135cm tall, whichever comes first

If you've got a backless booster seat in your car, you may want to replace it after today.

New rules have now changed how these seats - also known as booster cushions - are made across Europe. Some manufacturers are now banned from flogging certain models on the high street.

This is because the government believes backless car seats offer much less protection in the event of a collision.

Under the new guidelines, backless booster seats (which act like a cushion by placing children higher up on the back seat but without offering any extra protection) are only suitable for kids who are taller than 125cm and weigh more than 22kg.

If your child is below this weight/height, you can invest in a newer model, although this is not compulsory.

The Department for Transport advises that parents know the updated rules for using child seats.

Children must normally use a child car seat until they鈥檙e 12 years old or 135 centimetres tall, whichever comes first.

Children over 12 or more than 135cm tall must wear a seat belt. After this they must then use an adult seatbelt, according to the new rules.

If you do want to invest in a newer model, these are the best booster seats we've found for under £35.

3. Drive a company car? New changes to mileage rates

HMRC has published the latest advisory fuel rates (AFR) for company car users, effective from 1 March 2017 reflecting the constant trend in rising fuel prices

HMRC has published the latest advisory fuel rates (AFR) for company car users, effective from 1 March 2017 reflecting the constant trend in rising fuel prices.

Advisory fuel rates (or AFRs) are recommended reimbursement amounts for drivers reclaiming business mileage, usually for those in company vehicles.

HMRC reviews these rates every quarter, and publish revised figures in late February, May, August and November each year.

The previous rates can be used for up to one month from the date the new rates apply.

The rates only apply in the following circumstances:

  • Reimburse employees for business travel in their company cars; or
  • Require employees to repay the cost of fuel used for private travel.
  • These rates should not be used in relation to vans.
  • Hybrid cars can be treated as either petrol or diesel cars for this purpose.

Petrol rates

Engine size: 1400cc or less

  • Petrol - amount per mile: 11p
  • LPG - amount per mile:7p

Engine size: 1401cc to 2000cc

  • Petrol - amount per mile:14p
  • LPG - amount per mile: 9p

Engine size: Over 2000cc

  • Petrol - amount per mile: 20p
  • LPG - amount per mile: 14p

Diesel rates

Engine size: 1600cc or less

  • Diesel - amount per mile 9p

Engine size: 1601cc to 2000cc

  • Diesel - amount per mile 11p

Engine size: Over 2000cc

  • Diesel - amount per mile 13p

The HMRC Advisory Fuel Rates are available here.

4. Car tax rules are changing - 1 April 2017

High polluting vehicles will be charged more under new road tax plans

Road tax is set for a significant revamp from April this year, with many newly registered vehicles set to cost motorists more.

As a result of the changes, the amount of tax - or Vehicle Excise Duty (VED) as it鈥檚 officially known - that you鈥檒l have to pay will be based on your vehicle鈥檚 emission levels AND list price.

Currently, vehicles are divided into bands, based on their emission levels. Motorists with zero-emission vehicles pay nothing, while those with a car in the B band, for example, which emits between 101 and 110g/km of carbon dioxide, will pay £20 a year.

As of 1 April, your car tax will still be based on your band, however, the list price - the advertised price - of your vehicle will also be taken into account.

As a result, a flat standard rate of £140 will apply, with an additional £310 charged on cars with a list price over £40,000 between years two and five of ownership, no matter what their emissions levels.

Some pure electric cars will still not be subject to road tax, so remain a decent bet. However, premium electric cars come with a hefty price tag, so will likely incur the £310 premium car supplement.

The new rules ONLY apply to vehicles registered in the UK after the 1st April 2017. So your current car won鈥檛 be affected.

5. Speeding fines are changing

New speeding fines explained

Motorists caught out for speeding are to face tougher penalties from 24 April this year, as new sentencing guidelines take effect.

Drivers responsible for the most serious speeding offences will be handed harsher fines, under a series of strict new rules for district judges and magistrates, designed to make drivers "think twice".

The changes will see fines for motorists caught going well above the speed limit start from 150% of their weekly income, rather than the existing level of 100%.

For example, someone who is sentenced for driving at 101mph or faster in a 70mph zone will now be dealt with in a more severe bracket.

Drivers will also face points, or a disqualification depending on the offence.

Fines are determined in categories. A Band A fine is 50% of someone's weekly income, Band B is 100% and Band C is 150%.

The guidelines apply to all motorists and come into force on April 24, regardless of the date of the offence.

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