Situated half-way down Jermyn Street, in London’s historic St James’s district, British shirtmaker Turnbull & Asser has been making shirts for the great, the good and the not so good for 133 years. Just visit T&A’s bespoke shop on Bury Street, behind the Jermyn Street mothership, and you’ll get an immediate sense of the company’s deeply ingrained history.

The boards on which shirt patterns are cut are scarred and worn, the decor is muted, and an entire wall is lined with signed photos of Turnbull & Asser’s most recognisable customers. There’s Michael Caine, Daniel Craig and of course Al Pacino. Although Prince Charles (the reason why the brand has a much coveted Royal Warrant – more on that later) isn’t pictured, his regal presence hangs thick in the air. When I visited Turnbull & Asser late last year, to learn more about the process that goes into making each of the heritage company’s shirts – from bespoke and made-to-measure to ready-to-wear – a well-known English actor was in the house being fitted for his own bespoke shirt. The company’s glittering celebrity client list is testament to Turnbull & Asser’s enduring appeal both at home and abroad, but it’s here – in this quaint corner of the capital – that the magic really happens.

Though Turnbull & Asser is also famous for its sumptuous velvet smoking jackets (Churchill was such a fan he had three siren suits made from the fabric), cotton pyjamas, silk robes and its line of more traditional tailored pieces, it is for its shirts that the company is best known. The thing that sets Turnbull & Asser apart from other shirtmakers is not only its history, but also the fact that it produces both ready-to-wear and bespoke shirts, as well as made-to-measure shirts, which sit somewhere between the two. It is T&A’s ready-to-wear shirts, however, which are available from the Jermyn Street store, that form the bedrock of the business. Hundreds of shirts in shades of lilac, white, cream, periwinkle and charcoal are displayed in the specially made shelving units that line the interior of the shop.

Each shirt is built from no fewer than 33 individual parts, cuffs are hand-stitched, buttons are made of mother-of-pearl, and yokes are crafted from two separate parts. The yoke, incidentally, is the portion of fabric that sits across the shoulders at the top of the back. Even more impressive is the fact that the cotton used to make T&A’s shirts is cut on the bias. This means that each portion is cut against the natural grain of the fabric, which means that it hangs more fluidly and allows the wearer to move more freely. The collars are equally impressive. Buy a shirt from a less reputable shirtmaker and the likelihood is that the collar will have been fused, or glued, together. Not only will this make the shirt age more quickly, but it will also result in unsightly bobbles, bubbles and unmovable marks that will appear over the course of the shirt’s life – most noticeably after washing. Buy a ready-to-wear shirt from Turnbull & Asser, on the other hand, and you will get one with a collar that is ‘loose-lined’, meaning that the entire thing is sewn together and free to move more elegantly. It will also age more slowly. What’s more, the collar is finished with a barely perceptible curve in the portion that goes over the very top of the shoulders, which allows the collar to move more comfortably over the collarbone. It’s also, technically, very difficult to achieve. Even more impressive is that each ready-to-wear shirt comes with either a double cuff or triple button cuff. The latter style (which was originally introduced to the company’s cuff s to fit over wearer’s watches) has, over the decades, become a subtle signature of the house.

The majority of Turnbull & Asser’s shirts are cut from ultra-strong Egyptian cotton. The long staple of this type of cotton comes in two-fold 100 or two-fold 200 constructions, meaning that the fabric is incredibly durable and will last the test of time. The resulting shirts look almost iridescent. They’re silky to the touch and they have a bouncy and (most importantly) flattering character: shirts hang lightly against the skin, rather than cling. They drape over lumps and bumps rather than pull over them. When I choose my own ready-to-wear shirt, I tell Michael Searle – Turnbull & Asser’s store manager who is both uncommonly polite and unusually knowledgeable – that I think I’m a size 15 collar. With the glance of an eye he’s quick to inform me that ‘I think you may in fact be a size 16.5, sir, but let’s double check’. Searle is, of course, correct, and it’s at this stage, after trying the brand’s dummy shirt for size (T&A refuses to resell any shirts that have been unpacked, opened and tried on by anyone else, such is its dedication to perfection), that I choose my fabric. This time I opt for a simple white West Indian Sea Island Cotton. West Indian Sea Island is the most expensive of all cottons, due to the fact that the fabric is made from long, uniform fibres meaning that the fabric is both incredibly smooth, but also able to endure repeated washing. For my cuff, I opt for a classic three-button – this is Turnbull & Asser after all.

Collar-wise, the shirt fits like a dream, though given the extreme length of my spider monkey-esque arms, the sleeves are a little on the short side and the body a little bit wide. It’s a problem, I’m told, that I won’t experience with Turnbull & Asser’s new made-to-measure experience. It is Searle, I’m pleased to learn, who will guide me through my MTM shirt experience. Once again, I am asked to wear the dummy shirt to check my size, but I am also measured by Searle in several different ways to get my exact measurements so that the shirt can be customised to fi t me. I am able to choose the sleeve length (see my earlier ‘monkey arms’ comment), I can choose the fabric and there’s even an option to monogram my shirt: with up to three initials in the colour, font and position (cuff, hem or left breast) of your choice. It’s the ability to choose the fabric of your shirt that is perhaps the most satisfying part of the whole process. There are soft pastel Sea Island Cottons, bright two-fold 100 cotton poplins in soft Bengal and candy stripes, two-fold 200s in classic hues of cream and sky blue, and even classic cotton ginghams in natty shades of salmon and periwinkle. I’ve never actually owned a Bengal shirt, so I opted for a slightly wider take on the classic style, with a soft blue, off -lilac stripe.

The resulting shirt fits perfectly, the slightly wider Prince of Wales collar looks pleasingly old fashioned, and the arm length is perfect. After wearing the shirt over Christmas and washing it a few times, it retains the intensity of hue, softens slightly and shrinks in the sleeve. The good news is that my shirt was cut specifically to incur a little shrinkage, so after a couple of washes it fits like a dream (and makes me look very debonair indeed… according to my mum on Boxing Day).

For my final Turnbull & Asser experience, I am having a bespoke shirt made – it’s the most exclusive service that the marque offers. T&A has been making bespoke shirts for decades and former customers include Winston Churchill, President Ronald Reagan, Charlie Chaplin and Pablo Picasso. Steven Quin, Turnbull & Asser’s retail director, is looking after me in the company’s Bury Street bespoke atelier. Quin personally holds the company’s Royal Warrant, as the shirtmaker to His Royal Highness the Prince of Wales. Turnbull & Asser was awarded the warrant in 1980 and was one of the first companies to receive the honour. The bespoke Turnbull & Asser experience is second to none. ‘When a customer comes in to have a shirt made for himself, we listen to his requirements, take 15-20 measurements, and from those measurements we design a pattern that is entirely individual to that customer,’ says Quin. ‘The choice of collars and cuff s is infinite. The cuff can be moved by an eighth of an inch to make it more or less spread and the depth of the collar can be made deeper. You can choose the number of buttons on the cuff and it is angled so it sits neatly on the wrist.’ He continues, ‘Buying Turnbull & Asser shirts is a part of English heritage. We make the best shirts in the world.’

Given that this was my first experience of having a bespoke shirt made, I decided to keep things classic. I opted for a two-fold 200 white cotton poplin, an elegantly pointed Prince of Wales collar (when in Rome and all that) and a beautifully-finished one-button (mother-of-pearl, naturally) cuff, which has a dressy-yet-pared-back feel. Fit-wise, I opted for a slim cut, which was draped close to the body and worked, consequently, as perfectly under a jacket as it does under a slim cut cashmere jumper. Following two fittings, my shirt was ready – but this was not to be the end. Quin recommends laundering your bespoke shirt not one, not two, but three times, before bringing it back one last time for the final alterations to be made. It is this extraordinary attention to detail that sets Turnbull & Asser’s bespoke service apart. Once the final pattern is made it’s kept – like a set of doctor’s records, or a CV – in a special bag for whenever the customer wants to have another shirt made. It’s a pleasingly archaic touch that feels elegantly out of step with the digital age. ‘All our customers’ measurements are kept in their own individual shirt bag,’ says Quin. ‘It’s a pretty unique club that our customers are part of.’ A club I personally couldn’t be happier to be a member of.