Seiko Mods — Custom Seiko Watches for Sale

Discover Seiko mods, custom-built watches that combine Seiko’s legendary reliability with luxury-inspired styling. At Nomods, we offer prebuilt Seiko mods — professionally assembled, tested, and ready to wear. Choose from Royal Oak, Nautilus, Aquanaut and Petrichor styles. Each watch features premium components like sapphire crystals, NH movements, and fitted straps. Whether you’re buying a finished mod or planning your own build, NOMODS is your trusted Seiko modding source.

Shop By Best Sellers

Ausverkauft
Nomods Seiko mod – Royal Oak 37mm Silver
Seiko mod – Royal Oak 37mm Silver
€280,95 €227,95 Sparen 19%
Reduziert
Nomods Seiko mod – Royal Oak 37mm Rose Gold
Seiko mod – Royal Oak 37mm Rose Gold
€280,95 €219,95 Sparen 22%
Reduziert
Nomods Seiko Mod - Petrichor 37mm Silver
Seiko Mod - Petrichor 37mm Silver
€341,95 €280,95 Sparen 18%
Nomods Seiko mod - Nautilus Skeleton Silver
Seiko mod - Nautilus Skeleton Silver
€306,95

Shop Prebuilt Seiko Mods

Browse our collection of ready-to-wear Seiko mods. Professionally assembled with high-grade movements and components, each watch is unique and fully tested.

Royal Oak Seiko mods
Royal Oak Seiko Mod
Nautilus Seiko Mod
Nautilus Seiko Mod
Seiko Mod Petrichor 37mm
Seiko Mod Petrichor 37mm
Aquanaut Seiko Mod
Aquanaut Seiko Mod

Featured Seiko Mod Parts

Want to create your own build? Explore our Seiko Mod Parts hub for everything from dials and crystals to cases, crowns, and straps.

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Seiko Mods — Frequently Asked Questions

Are Seiko mods real Seiko watches?+
Yes. Our prebuilt Seiko mods use authentic Seiko/NH movements (e.g., NH35/NH36, NH70/71/72). Cases, dials, hands, crystals, and some accessories are high-quality aftermarket parts, professionally assembled by NOMODS.
Can Seiko mods be serviced like normal watches?+
Yes. Any competent watchmaker familiar with Seiko NH movements can service them (regulation, lubrication, parts replacement). Keep your order info so a technician can reference the exact movement and parts.
Which movement is best for a Seiko mod?+
NH35/NH36 are the most popular and reliable for daily wear. NH70/71/72 are used for skeleton builds, while NH34 adds a GMT hand and NH38 is a clean no-date option.
What case size should I choose — 37 mm or 39–41 mm?+
37 mm suits slimmer wrists and classic proportions; 39–41 mm gives a bolder, modern presence. Case size also influences dial diameter (28.5 mm for most 37 mm builds, ~30.8 mm for many 39–41 mm styles).
Are Seiko mods water-resistant?+
Many builds are designed to be water-resistant, but it’s only guaranteed if a watch is pressure-tested and rated after assembly. If water resistance matters, choose a rated model and avoid opening the case after purchase.
How much do prebuilt Seiko mods cost?+
Pricing varies by movement, case style, crystal, and finishing. Expect entry builds in the lower hundreds and premium skeleton or luxury-style builds running higher. Each product page lists exact specs and price.
Can I request changes to a prebuilt watch?+
Minor changes (strap, bracelet, or crystal profile) may be possible before shipping. More complex swaps depend on compatibility. Contact us with the product link and the change you’d like.

Seiko Mods Inspiration & Guides

Are Seiko Nautilus Mods Worth It? 7 Shocking Truths Every Watch Enthusiast Must Know
Are Seiko Nautilus Mods Worth It? 7 Shocking Truths Every Watch Enthusiast Must Know
Are Seiko Mod Watches Worth the Money? The Complete 2025 Guide
Are Seiko Mod Watches Worth the Money? The Complete 2025 Guide
The Seiko Nautilus Perfect for Watch Enthusiasts
The Seiko Nautilus Perfect for Watch Enthusiasts

Let customers speak for us

from 63 reviews
Perfect companion to the gunmetal 37mm Royal Oak case.

This dial compliments my 37mm Seikoak beautifully along with the rose gold hands. The fit was perfect and the gunmetal watch is one of my favorites.

Michael Kuper
Royal Oak Skeleton Seiko Mod Dial V2 – 28.5mm NH70/NH71/NH72 Rosegold
Royal Oak Skeleton Seiko Mod Dial V2 – 28.5mm NH70/NH71/NH72 Rosegold
Unexpectedly great and precise workmanship!

Unexpectedly great and precise workmanship! I'm ordering more!

Dima
Seiko mod – Royal Oak 37mm Silver
Seiko mod – Royal Oak 37mm Silver
As advertised and expected

As advertised and expected. Genuine TMI part.

Michael Kuper
Seiko NH72 TMI Automatic Skeleton Movement
Seiko NH72 TMI Automatic Skeleton Movement
Beautiful case and bracelet

Beautiful case and bracelet. All parts fit well, the only issue came when resizing the bracelet. I should have read through the website first - I hadn't read the warning to wash the bracelet in warm soapy water first and I had a screw become stuck. It all worked out fine in the end, just a minor annoyance. The 37mm size fits my 7-3/8" wrist much better than I thought it would. I like it so much that I ordered a SeikoNaut case/bracelet which I'm currently waiting for.

Michael Kuper
Gunmetal Royal Oak Seiko Mod Case – 37mm NH35/NH72
Gunmetal Royal Oak Seiko Mod Case – 37mm NH35/NH72
Great finish

The case is well made and polished. Extra screws are included which is appreciated.
Shipping was a little bit slower than I expected, but it happens.

Thomas
Silver Royal Oak Seiko Mod Case – 37mm NH35/NH72
Silver Royal Oak Seiko Mod Case – 37mm NH35/NH72
Excellent quality workmanship on the entire watch

Excellent quality workmanship on the entire watch. Bracelet is well polished and looks amazing!

Anonymous
Royal Oak 37mm Seiko Mod Extended 1.5x Link
Royal Oak 37mm Seiko Mod Extended 1.5x Link
Royal Oak 37mm case

Finishing on the case is 10/10, perfect for smaller wrists. I broke one of the pins when I was shortening bracelet but that was my fault (that was not a problem because there are enough links).
I had a few questions for the owner who responded very fast on my emails.

A.
Nomods
High quality case will be purchasing again in possibly the 37mm size.

High quality case waiting for two 1.5 links to complete the fitting due to having a large wrist.

TIM C.
Rose Gold Royal Oak Seiko Mod Case – 41mm NH35/NH38/NH70
Rose Gold Royal Oak Seiko Mod Case – 41mm NH35/NH38/NH70
Perfect fit

Perfect fit in my NH movement and petrichor case, thanks!

Sergio Recio
Royal Oak Skeleton Seiko Mod Dial V2 – 28.5mm NH70/NH71/NH72 Silver
Royal Oak Skeleton Seiko Mod Dial V2 – 28.5mm NH70/NH71/NH72 Silver
Bought the case

Bought the case. It is really a unique product that doesn't exist anywhere else in the market. For anyone who likes Royal Oak and like a smaller footprint, this is an unmissable offering. Thank you Nomods.

Kevin H
Gunmetal Royal Oak Seiko Mod Case – 37mm NH35/NH72
Gunmetal Royal Oak Seiko Mod Case – 37mm NH35/NH72
great

great

Anonymous
Royal Oak 37mm Seiko Mod Extended 1.5x Link
Royal Oak 37mm Seiko Mod Extended 1.5x Link
Perfect Seikoak mod

Everything was perfect. Shipping was fast and the product is of very good quality. In my opinion this is a the best Royal Oak mod you'll find on internet

Ismail Abdelmalki
Seiko mod – Royal Oak 37mm Silver
Seiko mod – Royal Oak 37mm Silver
love the watch

Absolutely love the watch, it look realy good and adjusting the band was really easy

lars de groot
Seiko Mod Royal Oak OEM Birch
Seiko Mod Royal Oak OEM Birch

Awesome watch

Tom
Seiko mod - Nautilus Skeleton Silver
Seiko mod - Nautilus Skeleton Silver
Very Reliable

Awesome watch! Excellent piece from these guys. This is the 3rd piece and I have never been let down:

H.
Seiko mod - Nautilus Skeleton Silver
Seiko mod - Nautilus Skeleton Silver