What Is a Stock Float? Float vs. Outstanding

A stock's float is the number of shares actually available to trade publicly: the shares outstanding minus insider stakes, restricted stock, and other closely held blocks that cannot change hands freely. Shares outstanding is the total count of shares a company has issued to investors; the float is the tradable subset — always the same size or smaller. Most definitions stop there; this page keeps going, into where each number comes from, with real counts from SEC-filing and IPO records.

One detail up front, the most useful thing on this page: float is an estimate, not a reported figure. Companies report shares outstanding in their SEC filings every quarter. No filing line item reports "the float." Data vendors and index providers each compute a float by deciding which holdings count as locked away, and their answers differ. Our market-data warehouse carries share counts straight from filings and listing records — and no float column at all. Every number below is a measured share count; any figure called "float" elsewhere is somebody's subtraction.

What is the difference between float and shares outstanding?

Three share counts sit in a strict ladder, each a subset of the one above it:

1. Authorized shares — the maximum the company's charter permits it to issue. A ceiling set in the corporate paperwork, raised only by shareholder vote.
2. Shares outstanding — every share actually issued and currently held by investors, insiders included. This is the count reported in SEC filings, and the one behind market capitalization and earnings per share.
3. Float — the outstanding shares free to trade publicly, with the rest sitting in hands that cannot, or realistically will not, sell into the open market on any given day.

The non-float concentrates in a few familiar places: founder and executive stakes (often restricted stock), early investors still inside a post-IPO lock-up (customarily around 180 days), parent-company and strategic blocks, and unvested employee shares. Shares a company buys back leave the outstanding count entirely — whether they are retired outright or held as treasury stock, they are neither outstanding nor float.

None of the three counts is fixed. A 4-for-1 forward split turns each share into four, scaling outstanding and float together; a reverse stock split shrinks both by the same multiple, ownership fractions untouched either way. What moves the float relative to outstanding is different traffic: lock-up expirations and insider sales add tradable shares, follow-on offerings mint new ones, and buybacks pull shares out.

Where do share counts come from? SEC filings

Shares outstanding is a reported fact with a paper trail. Every 10-K and 10-Q carries share counts — a dated snapshot on the filing's cover page, and the basic and diluted counts inside the income statement that per-share earnings are computed from — the latter averaged over the reporting period rather than counted on a single day, so the two can differ slightly. "Diluted" adds the shares that would exist if outstanding options, warrants, and convertibles turned into stock, and runs slightly above the basic count at most companies. Our income-statement records carry both. Three megacaps, each from its most recent quarterly filing on record through July 8, 2026:

SELECT tk AS ticker,
       argMax(period_end, (filing_date, period_end)) AS period_ended,
       argMax(filing_date, (filing_date, period_end)) AS filed_on,
       round(argMax(basic_shares_outstanding, (filing_date, period_end)) / 1e9, 2) AS basic_shares_b,
       round(argMax(diluted_shares_outstanding, (filing_date, period_end)) / 1e9, 2) AS diluted_shares_b
FROM global_markets.stocks_income_statements
ARRAY JOIN tickers AS tk
WHERE tk IN ('AAPL', 'MSFT', 'NVDA')
  AND timeframe = 'quarterly'
  AND filing_date <= '2026-07-08'
  AND basic_shares_outstanding > 0
  AND diluted_shares_outstanding > 0
GROUP BY tk
ORDER BY diluted_shares_b DESC

Read the top row: NVDA's filing for the quarter ended 2026-04-26, filed on 2026-05-20, reports 24.29 billion basic shares and 24.39 billion diluted. AAPL reports 14.75 billion basic shares, MSFT 7.43 billion. Each figure traces to a named filing on a dated row — the most common SEC filings walks through the documents these counts live in. The float version of each number appears in no filing. At a mature megacap nearly everything outstanding trades freely, and float estimates sit close to the outstanding count; at a fresh listing the two can sit very far apart — which is where the one clean float measurement in the data lives.

How does an IPO create the float?

On listing day, the float starts out near one knowable number: the shares actually sold in the offering. Everything not offered — founder stock, employee grants, venture stakes — is outstanding but not yet tradable, most of it inside a lock-up. That makes the IPO record a rare thing: a real float measurement, taken at the moment the tradable count is sharpest. Our listing records store shares offered alongside total shares outstanding at listing; the ratio is the fraction of the company the deal floated. Measured across US common-stock IPOs of $100 million or more that listed in the first half of 2026 with both counts on record:

SELECT count() AS ipos,
       round(quantileDeterministic(0.5)(max_shares_offered / shares_outstanding, cityHash64(issuer_name)) * 100, 1) AS median_pct_offered,
       round(quantileDeterministic(0.25)(max_shares_offered / shares_outstanding, cityHash64(issuer_name)) * 100, 1) AS p25_pct,
       round(quantileDeterministic(0.75)(max_shares_offered / shares_outstanding, cityHash64(issuer_name)) * 100, 1) AS p75_pct,
       countIf(max_shares_offered / shares_outstanding <= 0.30) AS floated_30pct_or_less
FROM global_markets.stocks_ipos
WHERE listing_date >= '2026-01-01'
  AND listing_date <= '2026-06-30'
  AND ipo_status = 'history'
  AND currency_code = 'USD'
  AND security_type = 'CS'
  AND total_offer_size >= 100000000
  AND shares_outstanding > 0
  AND max_shares_offered > 0
  AND max_shares_offered < shares_outstanding

Across 39 measured listings, the median deal offered shares equal to 30.2% of its recorded total — the public float opened as a minority slice of the company. The middle half of the deals floated between 17.3% and 47.7%, and 19 of the 39 floated 30% or less. A newly listed company's market capitalization can run several times the value of the shares that actually trade — that gap is the float-versus-outstanding distinction, priced. For a live case study of a brand-new float meeting the open market, see SpaceX's June 2026 listing.

What did 2026's big IPOs float at listing?

The same measurement, deal by deal — eight of the half's largest measured offerings, shares offered against the total recorded at listing:

SELECT issuer_name AS company,
       toString(listing_date) AS listed,
       round(max_shares_offered / 1e6, 1) AS shares_offered_m,
       round(shares_outstanding / 1e6, 1) AS shares_outstanding_m,
       round(100 * max_shares_offered / shares_outstanding, 1) AS pct_of_shares_offered
FROM global_markets.stocks_ipos
WHERE listing_date >= '2026-01-01'
  AND listing_date <= '2026-06-30'
  AND ipo_status = 'history'
  AND currency_code = 'USD'
  AND security_type = 'CS'
  AND total_offer_size >= 100000000
  AND shares_outstanding > 0
  AND max_shares_offered > 0
  AND max_shares_offered < shares_outstanding
ORDER BY total_offer_size DESC
LIMIT 8

The largest measured deal of the half, Innio N.V., offered 90 million of its 750 million recorded shares — 12% of the company floated at listing. The fractions vary widely, and two caveats travel with every row: the offered figure is the top of each deal's offered range, and the recorded outstanding count covers the listed line of stock — at a company with more than one share class it can understate the full count and overstate the floated fraction. The authoritative numbers live in each prospectus and later filings; the feed is the index, the filing is the record.

SELECT count() AS ipos_h1_2026,
       countIf(security_type = 'CS' AND total_offer_size >= 100000000) AS large_common_stock_ipos,
       countIf(security_type = 'CS' AND total_offer_size >= 100000000
               AND shares_outstanding > 0 AND max_shares_offered > 0) AS with_both_share_counts,
       countIf(security_type = 'CS' AND total_offer_size >= 100000000
               AND shares_outstanding > 0 AND max_shares_offered > 0
               AND max_shares_offered >= shares_outstanding) AS dropped_placeholder_rows,
       countIf(security_type = 'CS' AND total_offer_size >= 100000000
               AND shares_outstanding > 0 AND max_shares_offered > 0
               AND max_shares_offered < shares_outstanding) AS measured_ipos
FROM global_markets.stocks_ipos
WHERE listing_date >= '2026-01-01'
  AND listing_date <= '2026-06-30'
  AND ipo_status = 'history'
  AND currency_code = 'USD'

Why does a stock's float matter?

Trading needs shares that can change hands, and the float is that supply. Names with a thin float are widely observed to move more sharply on days of unusual demand than names with deep floats — the pattern low-float screens exist to catch. Days when a stock trades far above its own volume norm — what relative volume measures — are the days a thin float gets tested, and the sharpness runs in both directions: declines in low-float names can be as steep as the rallies, and in a very thin name the act of exiting a position can itself move the price — a risk profile worth knowing before it is experienced firsthand.

Index providers run on float too: the major US index families weight constituents by float-adjusted market capitalization, counting only the shares available to public investors. Two companies with identical market caps can carry very different index weights when one of them floats only a small fraction of itself.

Stock float FAQ

What is the difference between float and shares outstanding?

Shares outstanding is every share a company has issued that investors currently hold, and it is reported in SEC filings each quarter. The float is the subset free to trade publicly — outstanding minus insider, restricted, and other closely held stock. The float is always the same size or smaller, and it is an estimate rather than a reported line item.

What is a low float stock?

A low float stock has a small number of freely tradable shares — commonly a recent IPO still inside its lock-up period, a company with heavy insider or parent-company ownership, or simply a small company. There is no official cutoff. Low-float names are widely observed to trade with sharper price swings, in both directions, on days of heavy volume.

How does an IPO's float work?

At listing, the float starts out close to the shares sold in the offering; the rest of the company is outstanding but locked up or closely held. Across the 39 large US IPOs of the first half of 2026 with usable records, the median deal offered shares equal to 30.2% of its recorded total at listing. The float then grows as lock-ups expire and insiders sell.

Can a company change its float?

Yes, and it changes constantly. Lock-up expirations and insider sales move shares into the float, follow-on offerings create new tradable shares, and buybacks pull shares out of investors' hands — shrinking outstanding and float together whether the repurchased shares are retired or parked in treasury. Stock splits scale both counts by the same factor and leave the tradable fraction of the company unchanged.

Every table above is a stored query — expand the SQL under any panel to see exactly what was counted, or pull the same counts for any ticker by asking in plain English on the Strasmore terminal.