Cartier has built two icons that couldn’t be more different from each other. The Ballon Bleu is round, refined and relatively modern. The Santos is square, sporty and carries over a century of aviation heritage on its wrist. If you’re trying to decide between the two, the answer will come down to what you want your watch to do for you and how you want it to look while doing it.
Two Very Different Histories
The Santos came first, by a long way. In 1904, Louis Cartier designed a wristwatch for his friend Alberto Santos-Dumont, a Brazilian aviator who needed to check the time without taking his hands off the controls of his aircraft. That watch became one of the first men’s wristwatches ever made, and its square bezel with visible screws is still instantly recognisable today. The modern Santos de Cartier, relaunched in 2018 with updated proportions and Cartier’s QuickSwitch strap system, stays remarkably faithful to that original design.
The Ballon Bleu arrived much later, in 2007. Its name translates to “blue balloon,” a reference to the blue sapphire cabochon crown that appears to float within a curved protective arch on the side of the case. Where the Santos was born out of practical need, the Ballon Bleu was born out of pure design ambition. Cartier wanted to create a round watch that felt unmistakably theirs, and the result is a piece that looks like nothing else in the brand’s catalogue.
How They Look on the Wrist
This is where most people will make their decision, and the two watches couldn’t feel more different.
The Santos has a square case with polished edges, exposed screws on both the bezel and the metal bracelet, and a dial framed by those signature elongated side bars. It has a mechanical, almost industrial character to it, softened by Cartier’s Roman numerals and blue sword-shaped hands.
The medium size (35.1mm x 41.9mm) wears comfortably on most wrists, and the integrated bracelet gives it a sporty, modern presence. It’s the kind of watch you’ll notice on someone’s wrist across a table.
The Ballon Bleu takes the opposite approach. Its round case features smooth, pebble-like contours and a domed sapphire crystal that catches the light beautifully. There are no sharp edges here. The crown is tucked into that distinctive arched guard, giving the case a flowing, unbroken profile. In the popular 36mm size, it sits elegantly on the wrist and disappears under a shirt cuff more easily than the Santos. It’s the quieter of the two, but that restraint is part of its appeal.
If you want something with visual weight and a sportier edge, the Santos is your watch. If you’d prefer something softer, more polished and equally suited to a cocktail dress or a business suit, the Ballon Bleu will likely win you over.
What Powers Each Watch
Both collections offer a mix of quartz and automatic movements, but the spread is different.
The Santos de Cartier’s core automatic models run on Cartier’s in-house Calibre 1847 MC, a self-winding movement with a 40-hour power reserve and 100 metres of water resistance. That’s a genuine tool-watch spec, and it reflects the Santos’s roots as a practical timepiece. The slimmer Santos-Dumont models, on the other hand, tend to use quartz calibres or the hand-wound Calibre 430 MC in the XL size.
The Ballon Bleu’s automatic models are powered by Cartier’s Calibre 1853, which runs at 28,800 vibrations per hour and offers around 37 hours of power reserve. It’s a reliable movement, though the power reserve is slightly below the Santos. Smaller Ballon Bleu models (28mm and 33mm) are typically quartz-powered, making them thinner and lower maintenance. The range of movements across both collections means there’s something for buyers who want pure mechanical watchmaking and those who’d rather not think about winding.
For water resistance, the Santos has a clear advantage at 100 metres compared to the Ballon Bleu’s 30 metres. If you want a watch you can genuinely wear to the pool or the beach, the Santos is the safer bet.
UK Price Points for These Two Icons
Pricing is fairly comparable between the two collections, though the Santos commands a slight premium at most levels.
A stainless steel Santos de Cartier in the medium size currently retails at UK authorised dealers for around £6,550 to £7,100. The larger Santos on bracelet sits slightly higher, and two-tone or gold versions can push past £12,000. Pre-owned Santos models in steel typically trade between £5,500 and £7,000 depending on condition and whether box and papers are included.
The Ballon Bleu offers a slightly lower entry point. Quartz models in steel start from around £4,000 to £4,500, while the 36mm automatic in steel comes in at approximately £5,500 to £6,200 at retail. Pre-owned Ballon Bleu watches are generally more affordable on the secondary market, with steel automatic models trading from around £3,500 upwards.
Both collections scale up significantly once you add precious metals or diamond settings, so the entry-level pricing above reflects the most commonly purchased configurations.
How They Hold Their Value
This is where the Santos pulls ahead. The Santos de Cartier has been one of the strongest performers in Cartier’s entire range on the pre-owned market. According to secondary market data, the Santos has gained roughly 4.5% in market value over the past 12 months, bucking the broader trend of declining luxury watch prices. Cartier watches with the best resale value tend to be those with deep collector recognition and strong heritage, and the Santos ticks both boxes.
The Ballon Bleu performs respectably, retaining around 70% to 90% of its retail value depending on the material and specification. Gold and diamond-set references hold up better than steel. However, as a younger collection without the same heritage weight, the Ballon Bleu generally doesn’t appreciate in the way certain Santos or Tank references can.
If resale value matters to you, and you’re buying in steel, the Santos is the stronger investment. If you’re buying to wear and enjoy, both watches will serve you well for decades.
Which Cartier Suits You Best?
If you tend towards a sportier, bolder style on your wrist, the Santos is hard to beat. Its aviation history, distinctive square design and tool-watch water resistance make it versatile enough for everything from the office to the weekend. It’s also the better pick if you’re thinking about long-term value retention.
The Ballon Bleu is the watch for those who want something elegant, refined and a little more understated. It’s one of the few round watches in Cartier’s core collection, which makes it unique within the brand’s lineup. It also tends to be the more popular choice as a gift or a first luxury watch, thanks to its softer design and wide range of sizes that suit smaller and larger wrists equally well.
There’s genuinely no wrong answer here. Both watches carry the Cartier name, both are beautifully made, and both have earned their place as modern icons. The right one depends entirely on your taste.
If you already own a Cartier Ballon Bleu or Santos and you’re thinking about selling or part-exchanging, The Watch Exchange London can help. Get a free valuation to find out what your watch is worth today, or visit our store in Burlington Arcade, Mayfair, for an in-person assessment with same-day payment.
