How to Choose a Vintage Ladies' Rolex: Lady-Datejust 26mm or Midsize 31mm?

Lay a quarter on your wrist where a watch face would sit. A Rolex Lady-Datejust 26mm, the ladies' Datejust size for decades, is just a little wider than that coin. Now swap in a half dollar. At just over 30mm, it's close to the Datejust 31mm, the size collectors call the midsize. Five millimeters sounds small on paper. On the wrist, the first watch reads as jewelry and the second reads as a watch.

This guide covers the practical side of choosing one: which size suits the way you wear jewelry, what the bezel, bracelet and dial tell you, how to read a reference number, and what to check before you buy. The examples are watches from our own listings. For the story of why these watches have lasted, read our post on why vintage Rolex watches feel so timeless. This one is about the measurements.

Start with size: 26mm, 31mm or 34mm?

Size changes how a watch wears more than the dial or the metal does, so decide it first. A 26mm case wears like a piece of jewelry, and a 31mm case wears like a watch you can read at a glance. At 34mm you're past the traditional ladies' sizes and into a plainer, sportier watch that plenty of women prefer.

26mm: the vintage Lady-Datejust size

26mm is the size most people picture when they think of a vintage ladies' Rolex. Our reference 6517 is a 26mm ladies' Rolex with a stainless steel case, an 18k yellow gold fluted bezel, its original acrylic crystal with a cyclops lens over the date, and a screw-down crown. On the wrist, the gold bezel catches the light before you notice the dial.

The trade-off is legibility. A 26mm dial is small, and the date window is smaller still. If you check the time from across a dinner table, try one on before you commit. If you mostly want gold on your wrist that also tells time, 26mm is hard to beat.

Datejust 31mm: the midsize

The Rolex Datejust 31mm sits between the classic ladies' and men's sizes, and the size is still in Rolex's catalog today as the Datejust 31. Our reference 68273 has a 31mm stainless steel case, a sapphire crystal, all original factory parts and a two-tone Oyster bracelet in 18k yellow gold and stainless steel. The extra five millimeters give you a dial you can read without lifting your wrist, and the bracelet puts more gold on your arm than the 26mm does.

34mm: the Air-King

Rolex's Air-King reference 14000 has a 34mm steel case and a time-only dial with no date window. The one we've listed has a pink dial with Arabic numerals at 3, 6 and 9, on an Oyster bracelet. There's no gold on it at all, so it sits more easily with white gold and platinum than either Datejust.

If you wear a bracelet stack, size also decides the watch's job. A 26mm watch joins the stack as one more piece beside a tennis bracelet or a thin bangle. A 31mm watch anchors it, and the other pieces line up next to it. Decide which you want people to notice first: the watch or the stack.

Rolex Lady-Datejust 26mm, then and now

The Datejust arrived in 1945 as a 36mm watch. The Lady-Datejust followed in 1957 in a far smaller case, and for decades the standard Lady-Datejust measured 26mm. At Baselworld in 2015, Rolex announced a 28mm Lady-Datejust to replace the 26mm, and 28mm is the current size.

That matters when you compare old with new. A vintage ladies' Rolex Datejust in 26mm wears two millimeters smaller than the Lady-Datejust you'd try on in a store today. If the new one felt right, a vintage 26mm will feel daintier, and a 31mm midsize will feel a little bigger. If you can, try on both vintage sizes rather than using a modern watch as your guide.

Dial, bezel and metal

The fluted bezel

Rolex first put fluting on the Oyster in 1926. The grooves helped screw the bezel tightly to the case and keep water out. Today the fluting is decorative. In gold, the ridges throw light the same way a fluted gold ring does. A smooth bezel, like the one on the Air-King, is quieter and reads as plain steel.

Rolesor: steel and gold together

Rolex calls the combination of steel and gold Rolesor, a name it trademarked in 1933. Two-tone is the easiest way to wear a Rolex with gold jewelry, because the gold on the watch repeats the gold on your rings and bangles. Next to 14k jewelry, the 18k gold on a Rolesor watch looks a shade richer, though most people stop noticing once everything is on.

Oyster or Jubilee bracelet

The Oyster bracelet, which Rolex introduced in the late 1930s, has broad, flat three-piece links. The Jubilee, created for the Datejust in 1945, has smaller five-piece links that drape more like a chain. Our 68273 is on a two-tone Oyster, so the gold runs down the center links in a solid band.

The dial

Check originality before you fall for a color. Collectors value an original dial with honest age over a refinished one that looks new, and a refinished dial lowers what a vintage Rolex is worth. Ask the seller directly whether the dial is original. After that, color comes down to taste. Silver stays quiet, and a pink dial like the Air-King's is softer on the wrist than it sounds.

How to read a Rolex reference number

On a vintage Rolex, the reference number is engraved on the case between the lugs at 12 o'clock, and the serial number sits between the lugs at 6. The bracelet has to come off to see them, so ask the seller for photos rather than removing it yourself.

The number of digits tells you the era. Four-digit references, like the 6517, are the oldest you'll usually see. Five-digit references began in the late 1970s, and six-digit references are the current generation.

On five- and six-digit references, the last digit usually tells you the metal. A 0 means stainless steel, a 3 means steel and yellow gold (Yellow Rolesor), and an 8 means 18k yellow gold. Our 68273 ends in 3, and its bracelet is 18k yellow gold and steel. The Air-King 14000 ends in 0 and is all steel. Four-digit references don't follow this code, so the 6517's last digit won't tell you its metal.

The reference also hints at the crystal. Nearly every four-digit reference has an acrylic crystal, like the original one on the 6517. Acrylic has a soft, slightly domed look and scratches more easily, though light scratches can often be polished out. Five-digit references came with either acrylic or sapphire, and every six-digit reference has sapphire. The 68273 has sapphire.

What to check before you buy a vintage Rolex

Start with the numbers. The reference and serial on the case should match the paperwork, box or certificate that comes with the watch.

Then look at the case. Sharp, defined edges on the lugs suggest a case that hasn't been over-polished. When we choose a watch, balanced case condition without over-polishing is one of the things we look for.

Ask when the watch was last serviced and what was done. A vintage Rolex is a mechanical watch, and its service history tells you how it has been cared for.

Think about water, too. The Oyster case was built to keep water out, but gaskets age. Before you swim in any vintage watch, have a watchmaker pressure-test it. Here in Newport Beach, the simpler habit is to take it off before you walk down to the water.

Every watch we offer is inspected before it goes on the site, and the listings for our 6517 and 68273 state that an authentication certificate is provided.

Pick the size first. Once you know how much watch you want on your wrist, every other choice gets easier. Browse our vintage Rolex collection with that size in mind.

FAQ

What size is a vintage Rolex Lady-Datejust?

For decades, the Rolex Lady-Datejust had a 26mm case. Rolex replaced it with a 28mm version in 2015, so a vintage Lady-Datejust is usually 26mm, two millimeters smaller than a new one.

Is a 31mm Rolex too big for a small wrist?

Usually not. The Rolex Datejust 31mm, known as the midsize, is about the diameter of a US half dollar, and it wears as a readable everyday watch. If you want the watch to blend into a bracelet stack instead, try a 26mm first.

What does the last digit of a Rolex reference number mean?

On five- and six-digit Rolex references, the last digit usually indicates the metal: 0 for stainless steel, 3 for steel and yellow gold (Yellow Rolesor) and 8 for 18k yellow gold. Four-digit vintage references don't follow this code.

What should I check before buying a vintage Rolex?

Make sure the reference and serial numbers engraved between the lugs match the paperwork, ask whether the dial is original, look for crisp lug edges that suggest the case hasn't been over-polished, and ask for the service history. At Mama Bijoux, every watch is inspected before it's offered.

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