Levi's never printed a year on a 501. What it did do was change small details every few years, and collectors have spent decades matching those changes to dates. Learn the handful that show up in listing photos and you can place most pairs within a few years. Start with the tab, then the back pocket corners, the outseam, the care tag and the buttons. No single detail settles it, since tabs get cut off, buttons get replaced and reissues copy everything, so look for details that agree with each other.
The red tab
Levi's sewed the red tab into the right back pocket of the 501 on September 1, 1936. At first LEVI'S was woven in white capitals on one side only. Levi's own historian dates the one-sided tab to 1936–1952, and Heddels' collector guide says a one-sided tab means before 1951, so read it as a sign of an early 1950s or older pair. From the 1950s the name appears on both sides.
In 1971 the lettering changed from LEVI'S to Levi's, with only the L in capitals. The change followed the batwing logo Walter Landor's design firm drew in 1967. Since the E is the only letter that looks different, collectors call the older tab the Big E and the newer one the small e, and Levi's says the Big E became the accepted line for true vintage. That's why the Big E 501 and the small e 501 have separate pages here.
Two cautions. A red tab with only the registered mark on it is genuine, because Levi's makes a share of its jeans with a blank tab to protect the trademark. And Levi's brought the Big E back in 2018 for its premium lines, so a capital E alone doesn't make a pair old. Levi's suggests checking the tags inside, since jeans made before 1971 had none of them. Also check that the tab is there at all. Levi's says early discount stores and some wearers cut them off.
Hidden rivets and bar tacks
Next, the back pocket corners. Until 1937 the 501 had copper rivets showing on the outside of the back pockets. Customers complained that they scratched saddles, car seats and furniture, so in 1937 Levi's moved them under the denim, patented the method and hung a paper flasher on the pocket that read The Rivet's Still There. On a hidden-rivet pair the rivets show only from the inside of the pocket.
The hidden rivets wore through the denim anyway, and Levi's replaced them with bar tacks, the dense stitched bars you see on every 501 since. The date depends on who you ask. Levi's says 1966. Heddels gives 1964 or 1965, and Japanese Wikipedia's Levi's chronology says bar tacks started appearing in 1962 and hidden rivets were gone by 1967. Call it the mid-1960s. Hidden rivets with a Big E put a pair before that change, and bar tacks with a Big E put it between the mid-1960s and 1971.
Heddels adds one more 1960s clue. Until about 1969 a small V-shaped stitch ran down from the top of the waistband beside the top button. A Big E without it is likely from around the turn of the decade.
The outseam
Ask for a photo of a cuffed hem or the inside of the leg seam. A 501 with selvedge there, a clean white edge with a red line in Cone's denim, was woven on narrow shuttle looms. Levi's says Cone switched to wide looms around 1984, and Heddels quotes former Levi's designer Miles Johnson saying the 501 used selvedge until 1985. Japanese Wikipedia says Cone stopped weaving the narrow 29-inch fabric in 1983 and selvedge 501s ended around 1986, with non-selvedge pairs mixed in from about 1981. So a redline 501 is from the mid-1980s or earlier, and that covers plenty of small e pairs too. Our selvedge guide covers what else the edge does and doesn't tell you.
Non-selvedge 501s have an overlocked outseam instead. Heddels says the first ones, from about 1981 to 1984, used a copper-orange overlock thread, and later ones a white thread until 1993.
Back pocket stitching
Heddels dates small e 501s by how the back pockets are sewn on. Single-stitched pockets point to 1971–1978, and double-stitched pockets to 1978 or later. We've only found this rule in one guide, so use it to narrow a range rather than to settle one. The same guide says lemon yellow thread, in places like the coin pocket, the hem chain stitch and the arcuate, got rarer through the 1970s as copper orange took over.
Care tags and the patch
The FTC's Care Labeling Rule came in 1971, the same year as the small e, and from then on 501s have a care tag sewn into the outseam of the left leg. Heddels says the first ones have SF 207 on the top line. Before that, from about 1968, wash instructions were printed on the right pocket bag, and the patch said Care Instructions Inside Garment. A real Big E 501 with no pocket-bag printing and no care tag is from before 1968.
The care tag helps with later pairs too. Early tags say the jeans shrink about 8 percent, and from about 1980 or 1981 they say about 10 percent. Tags that say Care on Reverse and carry a red batwing logo point to the late 1980s. Tags with care symbols and written instructions run from about 1991 until Levi's closed its last US plants in 2002 and 2003.
Read the patch on the waistband if it's legible. Leather patches gave way to a card patch in about 1954 or 1955. Every Garment Guaranteed disappeared from the patch around 1962 or 1963. The XX after 501 was dropped in the late 1960s and came back in small letters in 1987.
Button-back numbers
Ask for a photo of the back of the top button. Heddels says most 501s from 1981 onward have a three-digit number there, through the 1990s pairs. The number is the factory, and 555 is the Valencia Street plant in San Francisco, which Levi's ran from 1906 until it closed in 2002. Heddels says 1950s pairs often have a letter such as K or S instead, and older Levi's jackets a one- or two-digit number. Levi's own reissues use three-digit stamps too, including 555, so the number tells you the factory more than the decade. Read our reissue guide before you trust one.
Putting it together
Here's a quick way through a listing once you have the photos.
- Big E, hidden rivets, leather patch. About 1954 or earlier, and a serious collector's pair.
- Big E, bar tacks, no care tag. Mid-1960s to 1971. Check the right pocket bag for printed wash instructions.
- Small e, redline outseam, single-stitched back pockets. 1971 to the late 1970s.
- Small e, redline, double-stitched back pockets. About 1978 to the mid-1980s. Our redline 501 page covers these.
- Overlocked outseam, three-digit button, written care tag. Late 1980s to 2002, like the 1990s USA 501.
Once you've placed a pair, measure it before you buy. Decades of washing move the waist and inseam a long way from the tag, and our measuring guide shows what to ask the seller for.
