IWC Watch Straps

Built-to-order leather straps for your IWC — Big Pilot, Pilot and Mark XVIII, Portugieser, Portofino, Ingenieur, Da Vinci and Aquatimer. Cut to your watch's exact lug width and sized to your wrist. Handmade to order and typically delivered in 2–3 weeks, backed by 1,970+ reviews (4.7-star average).

Custom leather watch strap made to order for an IWC, shown in brown Barenia

Custom IWC straps, made to your watch

Lug widths 8–30mm · Wrist sizes 5–12" · Reuse your IWC buckle
Made in 3–5 days · Delivered in 2–3 weeks

Shown in brown Barenia. Every leather below can be cut to your IWC.

Choose your leather ↓

Lug Width Finder · All custom straps · Notched (Ingenieur, Da Vinci) · Shell cordovan · Extra-long

Why some IWCs need a notched strap — and why the rest need the right reference

Two things go wrong on IWC straps. First, the widths move within a family: the Big Pilot 46 is 22mm but the Big Pilot 43 is 21mm, and the Mark XVIII is 20mm. Second, and stranger: the Ingenieur Automatic is 14mm and the Da Vinci 36 Moonphase is 11mm — on cases 40mm and 36mm wide. Those numbers are correct; the lugs are recessed under the case. Fit a plain strap at that width and it looks absurd, a narrow band floating under a wide watch. Those cases need a notched strap, cut to the full width of the case with a narrower tongue that drops into the lug gap.

IWC lug widths at a glance
IWC model Lug width
Big Pilot 46mm (IW5009 and similar) 22mm
Big Pilot 43 (IW3293 / IW3297 / IW3298) 21mm — not 22mm
Pilot Mark XVIII 20mm
Pilot Chronograph usually 21mm (some 20mm)
Pilot Spitfire 20mm or 21mm
Pilot Top Gun usually 21mm (some 22mm)
Portugieser 20mm or 22mm (Perpetual and Hand-Wound: 22mm)
Portofino 18mm or 20mm (smaller cases 16mm)
Da Vinci Perpetual mostly 19mm (some 20mm)
Da Vinci Chronograph 24mm
Da Vinci 36 Moonphase 11mm — recessed lug, needs a notched strap
Ingenieur Chronograph 20mm
Ingenieur Automatic 35 / 40 / 42 (IW3249 / IW3287 / IW3289 / IW3389) 14mm — recessed lug, needs a notched strap
GST Aquatimer 22mm

Widths above come from our reference database, which covers 1,100+ IWC references — and IWC moves widths between generations more than most brands. Check yours in the Lug Width Finder, or send us the reference number and we'll confirm before we cut.

Custom fit and leather options

Fit options off-the-shelf straps can't give you:

  • Ingenieur Automatic and Da Vinci 36 — recessed lugs — the lug gap really is 14mm (or 11mm), but the case is 40mm wide. Our corner-notched straps are cut to the full width of the case, with the corners notched away so a narrower tongue drops into the lug gap. It fills the case opening the way the original bracelet did.
  • Big Pilot on a smaller wrist — a 46mm case needs a strap sized to your wrist, not to the watch. We cut short lengths from 55/100mm, and extra-long to 125/185mm for wrists up to 12".
  • Portofino and dress cases — narrow widths from 16mm with a slim, low-profile taper that sits flush under a thin case.
  • Vintage IWC — wire lugs, odd widths and pocket-watch conversions. Tell us the reference or send a photo and we'll size it.
  • Reuse your IWC buckle — pick “use your own buckle,” send a photo, and we punch the strap to fit it.

Getting the length right: measure your best-fitting strap — the short (buckle) side and long (tail) side, each from the lug — and enter those numbers, or use our Bespoke Fit Calculator.

Customer photo: VGreen yellow crocodile strap fitted to an IWC Edison Electronic

“A lovely yellow crocodile strap that sets off the black tungsten carbide case of my IWC Edison Electronic… I love it!”
— Nicholas Scotchmer, verified buyer · Read more reviews

Which leather suits your IWC

Pilot and tool (Big Pilot, Mark XVIII, Spitfire, Top Gun, Aquatimer) — Barenia, Buttero, Badalassi wax or shark, usually 20–22mm: veg-tanned leathers that darken with wear, the way a pilot's strap should.

Dress (Portugieser, Portofino, Da Vinci) — shell cordovan, crocodile, lizard or Minerva box, usually 16–22mm.

Ingenieur and integrated cases — any leather you like, cut as a notched strap to the case width rather than the lug width.

A note on water: leather straps are made for everyday dry wear. If you swim or dive in your IWC, switch to rubber or fabric and keep the leather for dry land.

IWC strap FAQ

Why does my IWC Ingenieur say 14mm? Because it is 14mm. The Ingenieur Automatic's lugs are recessed under the case, so the gap the strap sits in is narrow even though the watch is 40mm wide. A plain 14mm strap will fit — and look wrong. What it needs is a corner-notched strap: full case width, with a 14mm tongue notched into it.

What lug width is the IWC Big Pilot? It depends on the case. The 46mm Big Pilot is 22mm, but the Big Pilot 43 (IW3293 and its siblings) is 21mm — one millimetre out, and the most common IWC ordering mistake. The Mark XVIII is 20mm again. Check your reference.

Portugieser — 20mm or 22mm? Both exist. The Perpetual Calendar and Hand-Wound references are 22mm; many of the automatics are 20mm. Check your reference in the Lug Width Finder before you order.

Vintage IWC — wire lugs or a pocket-watch conversion? Yes. Early IWCs often have fixed wire lugs, which need an open-ended strap rather than a conventional one. Send us a photo and we'll tell you which you need.