Maybe you've never bought a sofa before. Maybe you haven't bought one for a long time. So perhaps you foolishly imagine that you can just go in to a shop, select one you like, and have it delivered at your convenience. But it's just not that simple, as the man who phoned a morning radio show recently discovered. In his case, he had learnt to his astonishment that when Laura Ashley, the shop from whom he had bought a £1,000-plus sofa looked for cash on delivery, it meant delivery to its Welsh distribution centre, not his home in Dublin. It also added two weeks to the eight weeks between the time he had ordered his sofa and its arrival in his livingroom.

It is possible in some, but not most, stores that sell sofas to buy one off the shop floor and get it delivered a few days later. However, in most cases, it will take between four weeks and two months from the point at which you choose the style and fabric you want to the time you can relax on it in your home.

So be warned: if you want a new sofa for Christmas, you'd better go out and choose it right now. But do all sofa shops take the same length of time to deliver? Do English chains take longer? Does anyone specialise in sofas to order, but in a hurry?

First Sofa in Dublin's South William Street advertises a sofa upholstered in heavy cotton that comes in four different shades; it costs £770 for an average two-and-a-half seater. Says Patricia: "We do make the sofas ourselves here in Ireland, but we order a lot of fabrics in from Italy and the UK. It would take eight to 10 weeks for delivery. If you had ordered on September 22nd, it would be ready in the third week in November."

Arnotts has the same lead time according to its man on the furniture floor: "Generally, you'd have to order eight to 10 weeks in advance. We could have a few models on the floor for immediate purchase; we have about three or four at the moment ranging in price from £800 to £1,500 that have been on the floor for some time."

Clerys is a little more encouraging. It has what it calls "a reasonable selection" of discontinued models on the shop floor, and if one takes your fancy, it could be delivered to your home on the Tuesday of the following week. Its prices range from around £499 for a basic two-seater sofa to over £1,000 for a three-piece suite. But if you want to choose your own fabric and style, it will take four to six weeks before it is ready. And it could be longer coming up to Christmas. "Mid-October could be the deadline at this time of year; how long it will take depends on the different manufacturers," says the saleswoman there.

Crate & Barrel, the Dun Laoghaire-based store, gets its large, handsome and expensive sofas made in Newry, Co Down. They cost from around £2,200 up to £3,500 for a three-seater, and it will take 10 weeks from order to delivery.

It doesn't make any difference whether you order one of their very large sofas or something smaller, according to a saleswoman on the furniture floor. In Crate & Barrel's book, 10 weeks means 10 weeks - and if you want to get a sofa from them by Christmas, you had better order one straight away.

At Habitat, it can be a little more complicated, because its sofas are made in England. Delivery times vary from four to six weeks and eight to 10 weeks, depending on whether you order a standard model or one that is really made to order. "In certain models, we have four or five colours of a fixed type of fabric," explains a furniture saleswoman. "The Pacino, for example, comes in cord in five different colours, and if you order one of these, the sofa will be ready in four to six weeks.

"But if you wanted a made-to-order model, for example the Maxime, you can choose from a huge range of fabrics and colours, and that would have an eight-week lead time." Habitat doesn't, she explains, sell shop floor models until the line is discontinued, and would only have them to sell occasionally.

What if you wanted your sofa in four, rather than six weeks - is there anything you could to expedite matters? No, says the saleswoman. "We can't guarantee four weeks because the sofas come from the UK, and the ferry could affect delivery."

If you really are in a hurry for your sofa, quiz the person you're buying from closely about "four to six weeks". Sofas Unlimited in Newmarket Square, near St Patrick's Cathedral in Dublin makes its own sofas, but like everyone else, quotes four to six weeks as its delivery time. A man there adds that at this time of year, "it'd be closer to six weeks. And the cut-off for Christmas would be the end of October".

A salesperson with a charming French accent in Laura Ashley's Grafton Street shop confirms the company's policy about cash on delivery. When you order your sofa there - they cost from around £800 to £1,000-plus - you pay 25 per cent of the cost. "Then, when it is ready for delivery from Wales, you pay the balance of 75 per cent; you will have your sofa two weeks after paying everything." The shop quotes 10 weeks as the time taken between order and delivery to your door. "If you order now, you will have it by Christmas." Is there any chance of getting it by the end of November? "No; we can't say exactly when you would get it in December, but you'd have it before the 25th."

And finally, we found a shop that did deliver a made-to-order sofa in a hurry - well, in three weeks. Brian S Nolan in Dun Laoghaire quotes a time of six weeks if you ask how long it will take to get one from them. But one customer who badly needed a new sofa before visitors arrived asked if the job could be done quicker than that. He had to settle for a fabric a shade away from the one he wanted (it comes from the US, so it had to be one already in stock in Ireland), and the sofa was a few days later than the two weeks originally agreed. But having discovered how hard it was to get a sofa he wanted quickly, he was more than pleased when the finished sofa was delivered to his door in just under three weeks.