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IWC Portofino Hand-Wound Moon Phase IW516403 Slate Index Red Gold Leather 45mm - BRAND NEW

IWC Portofino Hand-Wound Moon Phase IW516403 Slate Index Red Gold Leather 45mm - BRAND NEW IWC Portofino Hand-Wound Moon Phase IW516403 Slate…

Reference IW516403

Full watch configuration

IWC Portofino Hand-Wound Moon Phase IW516403 Slate Index Red Gold Leather 45mm - BRAND NEW

$18,699.00
Requested condition
Brand New

By IWC

Sourced to order. We confirm the watch, condition and final price before purchase. Reference images shown.

Eligible watches: 90-day returns for store credit only. Brand-new watches and other exclusions are final sale. Return terms.

IWC Portofino Hand-Wound Moon Phase IW516403 Slate Index Red Gold Leather 45mm - BRAND NEW

IWC Portofino Hand-Wound Moon Phase IW516403 Slate Index Red Gold Leather 45mm - BRAND NEW

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IWC Portofino Hand-Wound Moon Phase IW516403 Slate Index Red Gold Leather 45mm - BRAND NEW

Catalogue watch price: $18,699.00 USD

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The IWC Portofino Hand-Wound Moon Phase IW516403 is a brand-new 45mm red gold dress watch featuring a refined slate dial with index hour markers, a matching red gold bezel, and an elegant leather strap — a compelling expression of IWC's Portofino line at its most romantic and technically accomplished.

The IW516403 stands out through its rare combination of a warm red gold case, an understated slate dial, and the poetic moon phase complication that has defined the Portofino collection's identity for decades; contact Bizak & Co. today to purchase this reference at the best price or to learn more about acquiring it online.

Compare it across every Portofino Hand-Wound Moon Phase reference we carry, or browse the full IWC collection at Bizak & Co.

Buy this Portofino Hand-Wound Moon Phase, trade in your current watch, or sell us yours. Contact Bizak & Co. to make an offer or request a fair-market valuation.

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The IWC Portofino Hand-Wound Moon Phase IW516403 is one of the most evocative timepieces in IWC Schaffhausen's modern catalogue, distilling more than a century of Swiss watchmaking tradition into a wristwatch that is simultaneously a precision instrument and a work of decorative art. The Portofino family was conceived to pair perfectly with relaxed elegance — inspired by the glamour of the Italian Riviera coastal village of the same name — and the moon phase complication elevates that DNA into something genuinely poetic, tracking the lunar cycle with the smooth, unhurried precision that only a hand-wound movement can convey.

At 45mm in red gold, the IW516403 makes an undeniably assured statement on the wrist. Red gold — an alloy richer and warmer in tone than standard yellow gold — lends the case and bezel a burnished, almost antique depth that photographs beautifully and ages even better. The substantial diameter ensures the slate dial has genuine visual real estate to breathe, and IWC's designers have used that space wisely: clean index hour markers keep the layout disciplined and legible, while the moon phase aperture anchors the lower half of the dial with an astronomical display that rewards close attention.

The slate dial is a masterstroke of restraint. Neither silver nor grey in a conventional sense, slate carries a cool, sophisticated neutrality that allows the warmth of the red gold case to assert itself without competition. The index markers sit precisely, creating a rhythm around the chapter ring that draws the eye naturally toward the center and then outward to the moon phase. Whether viewed under natural daylight or the warm glow of evening candlelight, the dial shifts character in a way that keeps the watch endlessly interesting.

Powering the IW516403 is a hand-wound movement — a deliberate, philosophically meaningful choice by IWC. Winding a watch by hand is an act of engagement, a daily ritual that connects the wearer to the mechanical heart of the timepiece in a way that automatic rotors cannot replicate. The hand-wound architecture also typically allows for slimmer movement profiles, contributing to wrist comfort despite the generous 45mm footprint, and it speaks directly to enthusiasts who value horological authenticity over convenience. The moon phase display, driven by this movement, advances with the quiet, mesmerizing precision that has made celestial complications a benchmark of fine watchmaking for centuries.

The leather strap completes the ensemble with understated sophistication, ensuring the IW516403 transitions seamlessly from a business dinner to a weekend cultural event. Leather remains the definitive companion to a dress watch of this caliber — supple, classic, and free of any visual noise that a bracelet might introduce, allowing full attention to fall on the red gold case and the drama of the slate dial.

Bizak & Co. is pleased to offer this IWC Portofino Hand-Wound Moon Phase IW516403 in brand-new condition at the best price available. Whether you are a seasoned IWC collector adding a statement moon phase to your rotation or a discerning first-time buyer seeking a heirloom-quality timepiece, this reference delivers exceptional value in both emotional and horological terms. Reach out to the Bizak & Co. team at bizakandco.com to purchase online or to speak directly with a specialist about this reference.

Technical Details
Reference
IW516403
Model
Portofino Hand-Wound Moon Phase
Movement
Manual
Case material
Rose Gold
Bracelet material
Leather
Dial
Slate with index hour markers
Case size
45mm
Requested condition
Brand New
FAQ

1. What makes the IWC Portofino IW516403 special?
The IW516403 combines a rare red gold case and bezel with a slate index dial and a hand-wound moon phase complication — a trio of attributes that few dress watches at any price point can match. It represents IWC's Portofino line at its most refined, blending celestial romance with disciplined Swiss craftsmanship.

2. What movement powers the IWC Portofino Hand-Wound Moon Phase IW516403?
The IW516403 is driven by a hand-wound mechanical movement, a deliberate choice that creates a more intimate connection between wearer and watch through the daily winding ritual. The movement drives the moon phase complication, advancing the lunar display with characteristic IWC precision.

3. What is the case size of the IWC Portofino IW516403?
The IWC Portofino Hand-Wound Moon Phase IW516403 features a 45mm red gold case, making it a generously sized dress watch with strong wrist presence. The red gold bezel frames the slate dial in a warm, richly toned surround.

4. Is the IWC Portofino IW516403 suitable for everyday wear?
The Portofino IW516403 is best suited to formal, business, and special-occasion wear given its 45mm red gold case and leather strap — hallmarks of a classic dress watch rather than a sports or tool watch. Collectors and connoisseurs who rotate their watches will find it an exceptional choice for elevated occasions.

5. What is the dial like on the IWC Portofino IW516403?
The dial is finished in slate — a sophisticated, neutral tone with cool undertones — and features clean index hour markers rather than Arabic numerals, lending the watch a sleek, contemporary formality. A moon phase aperture occupies the lower portion of the dial, adding astronomical depth to the otherwise restrained layout.

6. Is the IWC Portofino IW516403 a good buy and how can I purchase it from Bizak & Co.?
The IW516403 in red gold with a slate dial is a compelling buy for collectors seeking a distinguished moon phase dress watch with genuine precious-metal presence, available brand new from Bizak & Co. at the best price. Visit bizakandco.com or contact the Bizak team directly to buy online or speak with a watch specialist about this reference.

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Our five-year Bizak & Co. warranty covers manufacturing defects affecting mechanical operation under normal use, starting on delivery. It is separate from any remaining manufacturer warranty.

Exclusions include accidental damage, misuse, water damage, cosmetic damage, normal wear, loss and theft. Coverage and service availability for vintage or modified watches are confirmed in writing before purchase.

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90-Day Returns for Store Credit

Eligible watches may be returned within 90 days for store credit. Brand-new watches and other exclusions are final sale.

Read eligibility, condition requirements, and exclusions.

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U.S. overnight shipping is $100; international shipping is $500. Dispatch takes 2–3 business days after your wire clears. International transit times vary. Shipping details.

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