A SEIKO WITH A DIFFERENT KIND OF CALENDAR
Some watches keep time. This one keeps you looking.
This Seiko 6F26-8019 is a compact late-1980s quartz dress watch with a calendar display that refuses to blend into the background. Rather than placing the day and date in a conventional window, Seiko built them into the dial as part of its design: the day of the week follows a curved inner track, while a small date aperture sits neatly at 6 o’clock. The result is elegant, slightly eccentric, and unmistakably period Seiko.
The white dial is framed by bold black Arabic numerals and clean black hands, giving the watch excellent visual definition despite its detailed layout. A slim gold-tone bezel, elongated lugs, and compact 34 mm case create a formal silhouette without making the watch feel overly dressy. Turn it over and the stainless-steel case back is marked 6F26-8019, with serial 9D0387.
The 6F26 belongs to Seiko’s early analog-quartz generation, a period when quartz watches were becoming more precise while still retaining the decorative character of traditional dress watches. The serial beginning 9D is conventionally read as December of a year ending in 9. In the context of this caliber and its late-1980s design, December 1989 is the most plausible estimate, although the exact production date cannot be confirmed from the serial alone.
Inside is Seiko’s 6F26 analog-quartz caliber, configured for hours, minutes, day indication, and date. The movement’s current accuracy and battery condition have not been independently tested for this listing, so no performance or service claim is made.
A brand-new genuine black leather strap gives the watch a clean modern finish while preserving its original character. At just 7 mm thick, with a 40 mm lug-to-lug measurement and 18 mm lug width, it wears slim and neatly on the wrist. This is not a conventional three-hander—and that is precisely its appeal: a restrained vintage Seiko with an unusually expressive calendar and just enough visual oddity to make it memorable.
Three points to note
Estimated production date: December 1989, based on serial 9D0387 and the watch’s 6F26 caliber.
Measurements: 34 mm diameter, 36 mm including crown, 7 mm thick, 40 mm lug-to-lug, and 18 mm lug width.
Fitted with a brand-new genuine black leather strap; the case back is stainless steel and marked “BASE METAL / ST. STEEL BACK.”
- Brand
- Seiko
- Reference
- 6F26-8019
- Year
- 1989
- Gender
- male
- Movement
- Quartz, Seiko caliber 6F26
- Function
- hours, minutes, seconds, day, date
- Case
- 34 mm - Base metal bezel; case material not specified
- Case back
- Stainless steel back; marked 6F26-8019 and serial 9D0387
- Case excluding crown
- 34 mm
- Case with crown
- 36 mm
- Lug-to-lug
- 40 mm
- Thickness (crystal included)
- 7 mm
- Lug width
- 18 mm
- Dial
- White/silver dial with black Arabic numerals, day-of-week arc, date display at 6 o'clock, and black hands
- Strap / bracelet
- Brand-new genuine black leather strap
- Bracelet fit
- Fits up to 7.5 in wrist
- Buckle
- gold, not original
- Crown
- original
- Crystal
- mineral (condition: 10/10)
- Waterproof
- Not tested
- Box
- no
- Paper
- no
- Includes
- watch only
Condition report
Dealer assessment
This Seiko 6F26-8019 is presented in excellent vintage condition based on the supplied photographs. The gold-tone bezel and case surfaces show a clean overall appearance with light signs of age visible on the exterior; the stainless-steel case back has visible surface marks, including a fine line across the back. The white dial, black Arabic numerals, day-of-week track, date display, hands, and crystal are clean and clear. The brand-new genuine black leather strap and gold-tone buckle are fitted to the watch. The strap is a replacement and is not represented as original. The watch is quartz; keeping time accurately with a new battery. Water resistance has not been tested and should not be assumed.
25JAssessed in-house from the watch in hand. Full details on request.
