Citizen makes more watches than almost anyone, across more families than anyone can keep track of — Chandler, Corso, Promaster, Tsuyosa, Garrison, Brycen, Weekender and dozens more, with names that blur into each other and sometimes get swapped outright: we've seen the same field-watch reference sold as "Chandler" by one dealer and "Garrison" by another. So when the strap wears out, "what size does my Citizen take?" has no one-word answer.
But it has a two-step answer, and the first step is one most owners never learn.
Step one: Citizen tells you — on the product page
Citizen publishes the lug width in the spec panel of its own product pages. Open your reference on the brand's site and look for the "Lug Width" field, sitting right under the case width: the Chandler field watch shows 18mm there, the 40mm Corso three-hander shows 20mm, and so on across much of the catalogue. Dealer spec sheets usually reproduce the same field. Before you measure anything, look your reference number up — it's on your caseback — and read the number the manufacturer printed.
Step two: confirm it with a ruler anyway
Here's the honest part nobody else will tell you: the field isn't infallible. A hands-on reviewer found one Citizen listed at 20mm that measured a full millimetre wider in the metal; owners of another family have documented the reverse — a published 21mm that photographs and measures as 22mm. Two misses in both directions, on the manufacturer's own pages. So the method is field then ruler: look up the published number, then measure between the lugs — ten seconds — before you order. When the two disagree, the ruler wins. Or message us with your reference number and we'll confirm the size for you.
The anchor points — what the well-documented families take
| Model family | Lug width to select |
|---|---|
| Chandler field watch, 37mm (BM8180 family) | 18mm |
| Corso three-hand, 40mm (BM7496 family) | 20mm — larger Corso references are sold 22mm parts; check your reference's field |
| Promaster Diver core (BN0150, BN0151, BN0156, NY0040, BN0191/93, Fugu) | 20mm — see the full Promaster guide |
| Promaster oversized & instrument models (Aqualand, Skyhawk, Nighthawk types) | 21–23mm by reference — field + ruler mandatory |
| Tsuyosa | No published width — see the Tsuyosa guide |
| Ladies' and smaller references | Narrower still — measure before ordering |
Three things in that table deserve emphasis. The core Promaster divers are 20mm — confirmed by Citizen's own factory replacement strap and a stack of per-reference sources — despite charts in circulation claiming 18mm or 22mm for them; that correction has its own section in the Promaster guide. The Chandler's 18mm is the width most field-watch straps skip past on their way from "small" to "standard." And the oversized instrument models are where Citizen gets genuinely strange: owners inventory their own collections at 21mm, 23mm — several 23s — and even 25mm on one reference. Citizen uses more different lug widths than any brand we've covered, and the strap trade stocks about two of them.
A warning for the odd-width references: do not force the next size up. A 22mm strap squeezed into 21mm lugs takes a permanent set and is ruined for a true 22mm watch afterwards; an undersized strap lets the watch slide along the spring bar. If your Citizen measures 23mm or 25mm, it needs a strap made in that width — we'd rather say so than sell you the wrong part.
The best straps for a Citizen
1. Black curved FKM rubber — 18 through 22, every anchor in the table. The curved FKM rubber strap in black covers the Chandler's 18, the Corso and core Promasters' 20, and the 21s and 22s on the bigger models — including two widths most of the trade doesn't cut. On the divers it's the strap the water rating deserves; on the field watches it's the one the original never was: the Chandler's factory band drew an owner's complaint in print — stiff, scratchy, metal grommets and all — with the verdict that a decent strap is the first thing to buy. 125mm + 75mm, your choice of buckle and spring bars included, lifetime warranty on all our rubber.
2. Black with blue LuxLine® — for the blue dials. Blue runs through the Corso and Promaster ranges, and the LuxLine® strap in black with a blue centre line repeats it quietly. 20, 21 and 22mm — the Chandler's 18 sits outside its range, so keep that watch on the solid colours.
3. Leather — the dress-Citizen answer. The Corso is a leather watch by design and the Chandler wears brown or olive leather beautifully. Pick a shade in the leather strap collection that repeats something on the watch — confirm your width is selectable on the product page first (18mm Chandler owners: message us and we'll check) — and keep it away from the pool. Leather carries a 1-year warranty.
4. Every other colour, exactly sized. The full universal curved rubber collection runs 18–22mm across the colour range. The rule that never fails: repeat a colour the watch already wears, or stay black.
Fitting it
Standard spring bars across the families above — a two-minute job with any spring-bar tool. Two Citizen-specific tips worth keeping: the factory spring bars on some references are slimmer-tipped than typical aftermarket bars, so if a new strap develops a faint rattle, refit the original Citizen bars inside it. And order by the lug width from the spec field, never by measuring the buckle end of the old strap — factory straps taper, and the buckle number is the commonest wrong answer. Give the strap a firm tug at both lugs after any swap.
FAQ
What size strap does my Citizen take? Look up your reference number on Citizen's own site — the Lug Width field is in the spec panel — then confirm with a ruler between the lugs. The Chandler is 18mm, the 40mm Corso 20mm, the core Promaster divers 20mm; the oversized instrument models run 21–23mm by reference.
Is the published lug width always right? Almost always — but not always. Reviewers and owners have documented references where the printed figure was a millimetre off in either direction. The field is your starting point; the ruler is your confirmation. When they disagree, trust the ruler.
I've read the Promaster Diver takes 22mm — is that right? Not for the core divers: the BN0150/NY0040 family is 20mm, matching Citizen's own factory replacement strap. Some oversized Promaster references genuinely do take 21mm and up — which is exactly why the reference-by-reference check beats any brand-wide chart, including the ones that got this wrong.
One brand, every width — sized right the first time
More than 50,000 watch owners worldwide trust Helvetus with their straps, and Citizen owners get the full benefit of the range: 18 through 22mm cut exact — including the odd sizes the trade skips — with your choice of buckle in the box, and honest advice when your reference falls outside what we make. Rubber carries our lifetime warranty, leather is covered for a year, shipping is free worldwide with no import costs, and returns are easy. Check the field, check the ruler, and give the watch that never needs a battery a strap that lasts as long as it does.
