How to date vintage clothing

Start with the right question

“What decade does this look like?” is a good first guess, but styles were revived constantly — the 1970s borrowed from the 1930s, the 1990s from the 1970s. Reproductions are common too: Wikipedia notes that “vintage-inspired” pieces are usually modern, mass-produced interpretations. So the better question is: what is the earliest this could have been made, and what is the latest? Each clue below sets one of those limits.

1. Zippers: type and placement

Zippers are one of the most reliable clues because their history is well documented. Whitcomb Judson patented his “clasp locker” in 1893; Gideon Sundback's improved fastener went on sale in 1913; and B.F. Goodrich gave it the name “zipper” in 1923, using it on rubber boots. A sales campaign put zippers in children's clothing in the 1930s, and in 1937 the zipper won the “Battle of the Fly” against buttons in men's trousers (Wikipedia).

For women's clothing, the Vintage Fashion Guild's dating tips give these patterns:

Look at the pull tab too. Talon has made zippers in the US since 1894 and YKK in Japan since 1934, according to the Vintage Fashion Guild; Wikipedia adds that YKK restarted under that name after the Second World War and had about 45% of the world market by the 1980s. A brand name on the slider is a small clue to origin, not a precise date.

2. Seams and stitching

• Lockstitch versus chain stitch. Chain stitch came first; lockstitch seams are rarely found before 1870 (Vintage Fashion Guild).
• Hand and machine together. Hand and machine construction coexisted until the 1880s or later, so hand finishing alone doesn't mean a garment is very old.
• Overlocked (serged) edges. The serger was first patented by the Merrow Machine Company in 1889 and has been used to finish seams since the 1920s. The Vintage Fashion Guild treats it as one clue among many, not a cut-off on its own.
• Zigzag stitching. Patented in 1873; a home zigzag machine from Necchi was available from 1947.
• Hem tape generally indicates North American manufacture; hanging loops inside necklines are usually European in origin.

3. Cut

Cutting on the bias — diagonally across the grain, so the fabric drapes and clings — was championed by the French couturière Madeleine Vionnet from the 1920s and, by the early 1930s, defined the era's sleek, low-backed satin evening look (Wikipedia). Bias-cut slips and gowns are a hallmark of 1930s lingerie, though the technique has been revived many times since.

4. Fibers

5. Labels

Finally, read every label. A union label, a care label (required in the US from the early 1970s under the FTC's 1971 rule), an RN number or a fiber-content tag each has its own timeline. Our guide to reading the label covers these in detail, including ILGWU label versions; Cornell's Kheel Center notes the red, white and blue ILGWU label began in 1974.

A quick worksheet

1. Note the earliest possible date set by each clue (for example, “coil zipper: after 1940”).
2. Note the latest likely date (for example, “no care label: probably before the 1970s”).
3. Check for repairs and replaced parts before trusting a clue.
4. Where the clues overlap is your best estimate — state it as a range, such as “c. 1955–1963”.