'New law? Sorry, what new law is that?' inquired Madame from behind the counter of Vins de France, a little wine shop near the market square in Boulogne. I might as well have been talking about the invasion of the Visigoths for all she knew or cared about the prospect of les anglais arriving, en masse, each to buy 90 litres of wine (of which up to 60 litres can be sparkling), 20 litres of fortified wine, 10 litres of spirits and 110 litres of beer.

To find out what is available for day-trippers hurrying to take advantage of the new guide levels, which replaced the old duty-free allowances yesterday, I was doing some homework in Calais and Boulogne. There was little sign of excitement. At the Leclerc supermarket in Boulogne, an unexciting-looking Foire Aux Vins (Wine Fair) offering discount prices, was coming to an end on 31 December - just in time to head off the invasion of bargain-hungry Brits.

Only at Le Chais, a wine warehouse with outlets in Calais, Boulogne and Le Touquet, did they seem a little more clued up. Guy Vanikout has already reserved himself three places in the Commercial Centre at the Calais entrance to the Channel tunnel, which is expected to open next year. Even then he had not made any particular changes to the range to accommodate the hordes. He simply said that the prices of items such as beaujolais and some of the Bordeaux chateaux would be coming down in the new year.

The selection of wines in the French shops, supermarkets and hypermarkets is, not to put too fine a point on it, both limited and dismally drab. It is not just the pathetic selections, but the dreadfully old-fashioned feel of it all. Nothing seemed to have changed since I last did a pre-Christmas shopping expedition to Calais and Boulogne five years ago. Prices are generally badly displayed and, in some cases, not displayed at all. There are no staff on hand to help with questions, even though the level of knowledge of the average British buyer and the disproportionate amount of money he or she is prepared to spend would clearly justify such a presence. Above all, the range in every shop and supermarket is limited (to French wines) and, with the exception of Bordeaux, usually provided by indifferent negociants and co-ops rather than individual growers.

There are one or two bargains, however. First of all fizz. Because of the structure of the trade in France, French supermarkets all sell a premier prix (cut-price) champagne. These are in the region of Fr45 (pounds 5.49) at present compared with Britain's cheapest at pounds 7.99. With a price saving of pounds 30 per dozen bottles, it could be a case of never mind the quality, look at the label. Outside the premier prix champagnes, the acceptable, cheaper brands such as Jeanmaire, Fr94.50 (pounds 11.50) at Mammouth, or Alfred Rothschild, Fr79.95 (pounds 9.75) at Auchan, seem the best buys.

Non-champagne fizz offers similar savings. There is perfectly good sparkling Saumur such as Le Chais' Pol-Robert Thomas from Bouvet Ladubay at Fr27 (pounds 3.29) compared to over pounds 5 in the UK. The price of the seriously cheap fizz varies between Fr6.50 (79p) at Auchan to Fr7.80 (95p) at Le Chais, a saving of pounds 35 per case on Victoria Wine's pounds 3.69 for its cheapest fizz.

If price alone is the criterion, you can make savings in almost any area. Do not expect what you buy to be particularly drinkable, but the cheapest table wine comes in at around Fr5 a bottle (60p) at Continent in Calais, while the cheapest bordeaux is Fr9.45 (pounds 1.15) at Auchan, the cheapest beaujolais Fr9.95 (pounds 1.21) also at Auchan, and the cheapest Cotes du Rhone Fr7.80 (95p) at the PG supermarket. ('Un vignoble de caractere,' said the shelf talker, although at this price I have my doubts.) Start climbing the quality scale and you begin to hit prices that approach their English counterparts. As a general rule, the higher the price, the smaller the differential between French and UK prices.

A reasonable bordeaux such as Malesan is around Fr20 (pounds 2.45) at Auchan and Fr24.95 (pounds 3) at Mammouth and Continent, compared to about pounds 3.50 here; Mouton Cadet, the most popular bordeaux brand, varies from Fr44.60 (pounds 5.44) at Auchan and PG to Fr52 (pounds 6.34) at Mammouth, when you can buy it at Sainsbury's for pounds 5.95. Bordeaux is the one area in which the French super-and hypermarkets offer a far bigger range than their British counterparts. It may be worth bringing back some bordeaux, but you will need to shop around carefully, taking, say, Webster's Wine Guide and some of the more comprehensive British wine merchant lists (Justerini & Brooks, 071-493 8721, and Hungerford Wine Company, 0488 683238, for instance) to compare prices and vintages.

I was expecting the French stores to be full of 1984s and 1987 bordeaux, the two worst vintages of the decade, but apart from PG, which does have an inordinate number of 1987s (some of which are actually drinking well now), I was surprised at the number of bordeaux chateaux from fine vintages such as 1985, 1986, 1988, 1989 and 1990, particularly at Auchan and Mammouth. Burgundy, on the other hand, offers too many traps for the unwary such as Gevrey-Chambertin 1984 at Fr117.65 (pounds 14.35) or Vosne-Romanee 1987 at Fr123 (pounds 15) both from Mammouth.

The two most fruitful areas for exploration are beers and spirits. French and Belgian beers are considerably cheaper than their imported counterparts - not to be confused with French and Belgian beers brewed under licence in the UK, which are cheaper than the imports but not as good. Thus Kronenbourg costs the equivalent of Fr6.85 (84p) a litre at PG, compared to pounds 2.70 a litre in the UK, while 33 Export is Fr6.45 (79p) a litre compared to pounds 2.36 a litre in the UK - savings of around pounds 15 on those cases of 24 bottles of 25 centilitres.

The bigger French hypermarkets offer a wide range of spirits, the cheapest of which compare favourably with the UK. There are some substantial savings to be made on the better known brands, and in the luxury spirits and liqueurs bracket you may find some worthwhile bargains. Remy Martin VSOP Cognac, for instance, costs Fr159.95 (pounds 19.50) at Auchan compared to pounds 26.89 at Victoria Wine.

There are several things you should bear in mind before setting out across the channel to the off-licence. The new guide levels are not fixed limits like the old duty-free allowances; they represent the maximum you can bring in before Customs and Excise starts sticking the long nose of the law into your business. As long as you can prove the drink is not for commercial use, you can bring in as much as you like. So any amount of generous presents, for instance, or wines for weddings and parties, are all perfectly legitimate.

You will need a fully-loaded wallet, because reaching the guide level with even the cheapest and least cheerful gros rouge, the roughest spirit and the most watery beer, will still cost pounds 300. You will certainly have a fully-loaded car on the return journey: more than 13 cartons of wines and spirits and 18 of beer weigh in at roughly 425kg.

The exchange rate is, of course, crucial. Before Black Wednesday, shopping for wine looked as though it was about to offer bargains galore. It is a different ball game now with Fr8.20 or so to the pound, although the weakness of the lira makes Italian wines an attractive proposition - provided your car's suspension is in good nick.

If you are making a special cross-Channel trip, it might be worth waiting until the middle of the month, when the enterprising Battersea wine specialist, the Grape Shop, will be opening a branch at 85-87 rue Victor Hugo in Boulogne. 'The idea is to provide not just a range of French and new world wines,' says manager Martin Brown, 'but also the kind of personal service our Battersea customers get.' He says savings over UK prices will be between pounds 1.50 and pounds 3 a bottle on still and sparkling wines, and pounds 4 on malt whisky.

Calais: Mammouth, on the RN1 Boulogne road west of Calais. Continent on the Dunkerque road to the east of Calais. Le Chais, boulevard Jacquard, heading south past the town hall. PG, on the RN1 close to Mammouth and also east of Calais on the N43.

Boulogne: Leclerc Hypermarket, Zone Industrielle de la Liane, 62230 Outreau (RN1 to Paris). Auchan, Route Nationale 42, 62222 St Martin/ Boulogne (road to St Omer). PG Nord, route de Calais, 62200 St Martin/ Boulogne. PG Sud, route de Paris, 62200 Boulogne. Vins de France, 11 rue Nationale, 62200 Boulogne-sur-Mer. The Grape Shop, 85-87 rue Victor Hugo, Boulogne-sur-Mer.

Comparison of Bordeaux chateau prices in France and the UK

Les Forts de Latour 1990: pounds 18.41 Auchan, pounds 19.17 UK.

La Tour de Mons 1990: pounds 8.77 Auchan, pounds 8.99 UK.

Chasse-Spleen 1990: pounds 9.75 Auchan, pounds 11.80 UK.

Canon 1989: pounds 23.78 Mammouth, pounds 33 UK.

Ducru 1989: pounds 23 Continent, pounds 32 UK.

D'Issan 1989: pounds 13.73 Continent, pounds 16.50 UK.

Clos du Marquis 1988: pounds 13.66 Le Chais, pounds 10.90 UK.

Gloria 1988: pounds 9.08 PG, pounds 9.95 UK.

Pavie Decesse 1988: pounds 10.98 Mammouth, pounds 12.80 UK.

Cheval Blanc 1986: pounds 35.97 Auchan, pounds 56 UK.

Lynch Bages 1985: pounds 27.56 Mammouth, pounds 26 UK.

Comparative spirits prices

Gordons Gin: pounds 7.90 Auchan, pounds 10.49 UK.

Own-label or cheap gin brand: pounds 5.85 Mammouth pounds 9.15 UK.

Smirnoff vodka: pounds 7.02 Mammouth, pounds 9.89 UK.

Own-label or cheap vodka brand: pounds 4.26 Auchan, pounds 8.19 UK.

Famous Grouse whisky: pounds 10.53 Au chan, pounds 11.69 UK.

Own-label or cheap whisky brand: pounds 6.09 Auchan, pounds 9.23 UK.

Own-label or cheap brandy: pounds 6.09 Auchan, pounds 9.49 UK.

Bailey's Irish Cream: pounds 8.72 Continent, pounds 10.89 UK.

Grand Marnier: pounds 10.84 Leclerc, pounds 17.25 UK.

Exchange rate: Fr8.20 to pounds 1.

Comparative duty rates

Wine, 75cl: 1p France, 95p UK.

Fortified wine, 18 per cent, 75cl: 94p France, pounds 1.63 UK.

Spirits, 70cl: pounds 2.20 France, pounds 5.55 UK.

VAT: 18.6 per cent France, 17.5 per cent UK.

(Photograph omitted)