March is almost upon us and that means rich pickings for car buyers. The first of the month sees the introduction of the new 07 registration plates and dealers are scrabbling to be rid of 2006-registered models and hit end-of-year sales targets.

And that means motorists more interested in their bottom line than the numbers on their reg plate can make huge savings on leftover 56-registered stock — in effect buying a new car for up to £6,000 less that an identical vehicle with an updated numberplate.

“There’s always a sales lull before the new-reg plates hit the showrooms,” says Peter Cox of Glass’s car buying guides. “And with most people waiting for the 07 plates, buyers can get great deals if they’re prepared to take a 56-plated car.”

Car registration plates now change twice a year, in March and September. The first plates of the new year begin with 0, followed by the number of the year — so 07 for cars registered between March and September this year. The second new plates of the year begin with a 5, again followed by the year — 56 for cars registered from September last year. But it is the March change that brings the biggest sales surge.

From next weekend dealers can look forward to a flood of customers keen to snap up the 07-registered models with total new car sales expected to exceed 400,000, according to the Society of Motor Manufacturers and Traders (SMMT). But in February the showrooms are dead. This is the quietest month for dealers and the SMMT predicts there will be just 75,000 new car sales this month across the industry.

With dealers short of customers and desperate to shift their remaining 2006 stock to meet those all-important sales targets and claim their bonus, they are prepared to slash thousands of pounds off the list price of a new car to ensure a quick sale.

Where manufacturers are replacing an old model to time with the registration plate change, consumers have even more room for manoeuvre. Honda is now offering a blanket £2,000 off all previous-model CR-Vs, for example, since the updated model arrived in showrooms last month. And with the new-reg plates due later this week, consumers could expect to be able to double that discount.

We found a Mercedes-Benz CLK 200 Cabriolet (list price £36,328) for £29,999; a Skoda Octavia Sport (list price £17,240) for £14,995, and a Subaru Legacy 2.0 R Sports Tourer (list price £17,995) for £14,995.

There is one downside and that is depreciation, since you are, on paper, buying an older car. “There will be a difference in the depreciation even of two cars that were built no more than a week apart, where one is a 56 plate and the other a 07,” says Cox. But with registration plates changing twice a year, the difference is increasingly small, and usually nothing in comparison with the original discount.

Matthew Coleman, 39, a specialist in environmental law from Cornwall, bought his preregistered 06 Fiat Panda just before the registration plates changed last September. “The discount was too much to resist,” he says. “I saved 25% off the list price.

Now I’m recommending it to all my friends.”

None of this means that buyers should forget the traditional means of finding a bargain: researching properly, deciding exactly what car suits their needs, shopping around for a good finance package, and above all not being afraid to haggle. According to recent research, buyers who haggle get an average £1,578 knocked off the price of their new car. The biggest discounts were found at Citroën, where buyers negotiated an average £2,883 off the list price.

As any good haggler knows, timing is everything — and now could well be the perfect time.

How to haggle: the psychology of wearing a dealer down

Neal Bircher and Patrick MacManus — aka the Car Hagglers (www.carhagglers.com ) — are car dealers turned consumer champions. Here are their top tips for snaring a bargain:

Be nice Maintain a polite, approachable manner, don’t be confrontational. Put a dealer’s nose out of joint and you can kiss goodbye to a decent deal

Expect a discount There is always a discount available but a dealer will always initially claim there isn’t

Get quotes aplenty Call at least five dealers for initial quotes then use the best one as ammunition in the haggling process, squaring dealers up against one another. Check websites such as www.timesonline.co.uk/driving for latest deals

Don’t reveal your budget Never say how much you’re prepared to spend. That only lets the dealer know what he can get away with

Pass the buck There’s a trick in the trade called “higher authority” which is when the sales person claims they’ll have to check with their manager. Two can play that game. Control the negotiation by claiming you need to check with your spouse or business partner

Enjoy the silence If you think the dealer has more to offer, fall silent and pretend to ponder. Sensing they’re getting close, the dealer will be tempted to better the offer

Don’t meet them halfway When a dealer feigns a gesture of goodwill by offering to meet you in the middle, don’t fall for it

Never accept the first offer Once a dealer makes you an offer, don’t say anything except: “Surely you can do a bit better than that?”

Keep it simple If you want extras, add them to the car before you start haggling. Trying to get things thrown in after you’ve reached stalemate won’t help

If all else fails, leave If you still think there’s a better deal to be had, take the dealer’s contact details and go. Call the next morning and say you still want to buy the car but only at your price