What Is Short Interest? A Data-Backed Guide

Short interest is the total number of a stock's shares that have been sold short and not yet bought back — the running balance of open short positions, reported to FINRA twice a month. It is the market's standard gauge of how heavily traders are positioned against a stock, quoted in shares and usually read through two ratios: days to cover and short percent of float. Every figure on this page comes from that same regulatory dataset, with the exact query behind each number one click away.

What Is Short Interest in Stocks?

A short sale inverts the usual order of a trade: a short seller borrows shares, sells them at today's price, and aims to buy them back later at a lower one. Buying the shares back — "covering" — closes the loop and returns the borrowed stock to its lender. Until that happens the position stays open, and every open short position at every brokerage counts toward the stock's short interest.

Short interest is a level — an outstanding balance measured at a point in time, like the balance on a loan. It rises when new shorts open, falls when existing shorts cover, and says nothing by itself about any single day's trading. Two normalizations make the raw share count comparable across stocks: short percent of float, which divides it by the shares realistically available for public trading, and days to cover, which divides it by average daily volume — the second is measured across the whole market below.

One risk note belongs in any definition: a short position loses money when the price rises, and a stock's price has no ceiling, so the potential loss on an uncovered short is unlimited — unlike a long position, where the maximum loss is the purchase price.

How Is Short Interest Measured and Reported?

Short interest is a regulatory disclosure, not an exchange feed. Twice a month — once mid-month, once at month-end — FINRA, the securities industry's self-regulatory body, requires brokerage firms to report every open short position on their books as of a scheduled settlement date. The filings are compiled into one file per settlement date and published on a lag of days to weeks. Here is what the most recent file on record holds:

WITH (SELECT max(settlement_date) FROM global_markets.stocks_short_interest) AS latest
SELECT toString(latest) AS latest_settlement,
       count() AS tickers_reported,
       round(sum(si) / 1e9, 1) AS total_shares_short_b
FROM
(
    SELECT ticker, max(short_interest) AS si
    FROM global_markets.stocks_short_interest
    WHERE settlement_date = latest
    GROUP BY ticker
)

As of the 2026-06-15 settlement, the file covers 22178 tickers carrying a combined 55.8 billion shares of open short positions — the US equity market's short book in one twice-monthly snapshot.

The cadence has a practical consequence: whatever short-interest number you read today describes positioning as of the last settlement date, one to several weeks in the past. We measured each recent settlement's exact publication lag — including one print that had not arrived at all — in why short interest data is always two weeks old; the short version is that "current" short interest is never current.

A Worked Example: Tesla's Short Interest

Definitions stick better with a real ticker attached. The panel below tracks Tesla at every settlement date over the last two years — short interest next to the average daily trading volume published in the same file.

SELECT settlement_date,
       round(max(short_interest) / 1e6, 1) AS short_interest_m_shares,
       round(max(avg_daily_volume) / 1e6, 1) AS avg_daily_volume_m_shares
FROM global_markets.stocks_short_interest
WHERE ticker = 'TSLA'
  AND settlement_date >= today() - INTERVAL 2 YEAR
GROUP BY settlement_date
ORDER BY settlement_date

As of the 2026-06-15 settlement, 78.2 million TSLA shares were sold short, against 48.8 million shares of average daily volume. At the start of the window the short balance stood at 104.5 million. Count the data points: 47 settlement dates in two years — two per month, and nothing in between.

What Is Days to Cover?

Days to cover — also called the short interest ratio — divides short interest by average daily trading volume. It answers one question: at the stock's normal pace of trading, how many full sessions of volume would it take for every open short to buy back? The FINRA file computes the ratio for you, with one convention worth knowing: it is reported with a floor of 1.00 and never prints below it.

SELECT settlement_date,
       round(max(days_to_cover), 2) AS days_to_cover
FROM global_markets.stocks_short_interest
WHERE ticker = 'TSLA'
  AND settlement_date >= today() - INTERVAL 2 YEAR
GROUP BY settlement_date
ORDER BY settlement_date

Run the math on Tesla's latest row: 78.2 million shorted shares over 48.8 million shares of typical daily volume works out to the file's own figure of 1.6 days to cover. That is the classic mega-cap shape: a share count that sounds enormous in isolation sits on top of deep daily liquidity, and the ratio stays in the low single digits. Judging whether any reading is high needs the market-wide context below.

What Counts as High Short Interest?

There is no official threshold — "high" is a market convention, and the honest way to calibrate it is to measure the whole field. The screen below takes every liquid name in the latest settlement file (at least one million shares of average daily volume) and summarizes the days-to-cover distribution:

WITH (SELECT max(settlement_date) FROM global_markets.stocks_short_interest) AS latest
SELECT count() AS liquid_tickers,
       round(quantileExact(0.5)(dtc), 1) AS median_days_to_cover,
       round(quantileExact(0.9)(dtc), 1) AS p90_days_to_cover,
       min(dtc) AS lowest_days_to_cover
FROM
(
    SELECT ticker, max(days_to_cover) AS dtc, max(avg_daily_volume) AS adv
    FROM global_markets.stocks_short_interest
    WHERE settlement_date = latest
    GROUP BY ticker
)
WHERE adv >= 1000000

Across 2953 liquid tickers, the median is 2.6 days to cover and the 90th percentile is 7.1 days; the lowest value prints 1, the file's floor. Bucketing the same screen shows where the crowd sits:

WITH (SELECT max(settlement_date) FROM global_markets.stocks_short_interest) AS latest
SELECT multiIf(dtc < 3, 'Under 3 days',
               dtc < 5, '3-5 days',
               dtc < 10, '5-10 days',
               '10+ days') AS days_to_cover_bucket,
       count() AS tickers,
       round(100.0 * count() / sum(count()) OVER (), 1) AS pct_of_tickers
FROM
(
    SELECT ticker, max(days_to_cover) AS dtc, max(avg_daily_volume) AS adv
    FROM global_markets.stocks_short_interest
    WHERE settlement_date = latest
    GROUP BY ticker
)
WHERE adv >= 1000000
GROUP BY days_to_cover_bucket
ORDER BY min(dtc)

A majority of liquid names — 55.9% — sit under three days to cover, while a ratio of ten days or more puts a stock in a bucket holding just 3.4% of the field (101 tickers). Against that backdrop, a couple of days to cover reads as routine, and a double-digit ratio marks a genuinely crowded short position.

Market participants watch a high reading in two opposite ways, and both are descriptions of positioning rather than forecasts. Read one: a large short book represents many traders positioned for a decline — a measure of bearish conviction. Read two: every open short is a future buy order, and past squeeze episodes — GameStop in January 2021 is the reference case — paired crowded short positioning with sharp rallies and a rush of buy-to-cover orders. The same number feeds both stories, and nothing in it says which one plays out.

Is Short Interest the Same as Short Volume?

No — and the two are confused constantly. Short interest is the level defined above: open positions outstanding at a settlement date, twice a month. Short volume is a flow: the number of shares sold short during a single trading day, published daily from a separate FINRA dataset. A trader who shorts at 10 a.m. and covers by 2 p.m. adds to that day's short volume and never touches short interest — and much of daily short volume is routine market-maker activity rather than directional bets. The two metrics answer different questions on different clocks; we put real numbers on the distinction, one ticker with both datasets side by side, in short interest vs. short volume.

Short Interest FAQ

What is a high short interest?

There is no official cutoff. Measured at the latest settlement, the median liquid US ticker shows 2.6 days to cover, and only 3.4% of liquid names run ten days or more. By convention, a double-digit short percent of float is commonly described as heavily shorted.

How often is short interest updated?

Twice a month. FINRA schedules a mid-month and a month-end settlement date, brokers report open short positions as of each date, and the compiled file is published days to weeks later — the freshest print always describes the market as it stood at the last settlement.

What is days to cover?

Short interest divided by average daily trading volume: the number of full sessions of typical volume it would take for every open short to buy back. Tesla's latest print works out to 1.6 days, and the FINRA file reports the ratio with a floor of 1.00.

Is short interest the same as short volume?

No. Short interest counts open positions outstanding at twice-monthly settlement dates — a level. Short volume counts shares sold short during each single trading day — a flow, published daily. See short interest vs. short volume for both datasets measured on one ticker.

Every panel above is a stored query — open the SQL beneath it, swap in any ticker you follow, and re-run it on the Strasmore terminal to pull the same short interest fields in seconds.