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Fastenal Co

FAST
Exchange
Nasdaq
Industry
Retail-Building Materials, Hardware, Garden Supply
SEC CIK
0000815556

In the last 90 days, Fastenal Co insiders filed 0 open-market purchases and 1 sale; 1,469 institutions reported holding it in 13F filings for Q2 2026, worth $47.1B in total; no superinvestor holds it.

Four kinds of short-selling data, each measuring something different:

  • Short interest: shares sold short and not yet bought back, as of a settlement date. FINRA publishes it twice a month, about eight business days after the settlement date.
  • Daily short volume: shares sold short each day in off-exchange trades reported to FINRA. It counts trades, not open positions, and is published the next day.
  • Fails-to-deliver: shares not delivered by the settlement date. The SEC publishes them twice a month, about two weeks late.
  • ATS (dark pool) volume: weekly volume on alternative trading systems and other off-exchange venues. FINRA publishes it two to four weeks after the week.

More in the glossary.

Short interest

Shares sold short and not yet bought back, from FINRA, on every settlement date in the last two years.

Short interest
38.3M
Shares, settlement Oct 30, 2026
Change
+1.28M
+3.5% vs. Oct 15, 2026
Days to cover
5.12
Short interest ÷ average daily volume
Average daily volume
7.48M
Shares, as reported by FINRA
Short interest by settlement date
Oct 31, 2024: 13,265,886 sharesNov 15, 2024: 12,782,283 sharesNov 29, 2024: 12,034,574 sharesDec 13, 2024: 11,307,146 sharesDec 31, 2024: 12,053,138 sharesJan 15, 2025: 12,244,950 sharesJan 31, 2025: 13,157,166 sharesFeb 14, 2025: 13,516,691 sharesFeb 28, 2025: 13,651,131 sharesMar 14, 2025: 13,729,531 sharesMar 31, 2025: 14,221,090 sharesApr 15, 2025: 14,450,378 sharesApr 30, 2025: 14,684,319 sharesMay 15, 2025: 14,207,192 sharesMay 30, 2025: 28,005,205 sharesJun 13, 2025: 29,772,035 sharesJun 30, 2025: 27,847,271 sharesJul 15, 2025: 25,333,413 sharesJul 31, 2025: 25,447,460 sharesAug 15, 2025: 24,709,243 sharesAug 29, 2025: 25,224,369 sharesSep 15, 2025: 24,264,136 sharesSep 30, 2025: 25,848,771 sharesOct 15, 2025: 23,784,347 sharesOct 31, 2025: 26,285,149 sharesNov 14, 2025: 27,692,749 sharesNov 28, 2025: 29,427,595 sharesDec 15, 2025: 31,452,298 sharesDec 31, 2025: 31,434,778 sharesJan 15, 2026: 31,511,673 sharesJan 30, 2026: 34,665,326 sharesFeb 13, 2026: 33,154,548 sharesFeb 27, 2026: 31,926,847 sharesMar 13, 2026: 31,136,708 sharesMar 31, 2026: 27,514,034 sharesApr 15, 2026: 24,252,255 sharesApr 30, 2026: 24,523,768 sharesMay 15, 2026: 28,159,863 sharesMay 29, 2026: 28,459,231 sharesJun 15, 2026: 31,320,552 sharesJun 30, 2026: 30,905,562 sharesJul 15, 2026: 31,475,902 sharesJul 31, 2026: 35,899,233 sharesAug 14, 2026: 31,204,882 sharesAug 31, 2026: 34,649,070 sharesSep 15, 2026: 35,653,332 sharesSep 30, 2026: 34,618,329 sharesOct 15, 2026: 37,031,117 sharesOct 30, 2026: 38,315,307 shares
Short interest in FAST by settlement date
Settlement dateShort interestChangeChange %Avg. daily volumeDays to cover
Oct 30, 202638.3M+1.28M+3.5%7.48M5.12
Oct 15, 202637.0M+2.41M+7.0%8.73M4.24
Sep 30, 202634.6M−1.04M−2.9%7.53M4.60
Sep 15, 202635.7M+1.00M+2.9%6.17M5.78
Aug 31, 202634.6M+3.44M+11.0%5.52M6.27
Aug 14, 202631.2M−4.69M−13.1%7.88M3.96
Jul 31, 202635.9M+4.42M+14.1%8.32M4.32
Jul 15, 202631.5M+570.3K+1.9%9.25M3.40
Jun 30, 202630.9M−415.0K−1.3%8.24M3.75
Jun 15, 202631.3M+2.86M+10.1%6.51M4.81
May 29, 202628.5M+299.4K+1.1%6.90M4.12
May 15, 202628.2M+3.64M+14.8%6.48M4.35
Apr 30, 202624.5M+271.5K+1.1%6.18M3.97
Apr 15, 202624.3M−3.26M−11.9%8.48M2.86
Mar 31, 202627.5M−3.62M−11.6%8.40M3.28
Mar 13, 202631.1M−790.1K−2.5%7.88M3.95
Feb 27, 202631.9M−1.23M−3.7%6.43M4.96
Feb 13, 202633.2M−1.51M−4.4%10.1M3.29
Jan 30, 202634.7M+3.15M+10.0%10.3M3.36
Jan 15, 202631.5M+76.9K+0.2%8.56M3.68
Dec 31, 202531.4M−17.5K−0.1%6.94M4.53
Dec 15, 202531.5M+2.02M+6.9%6.93M4.54
Nov 28, 202529.4M+1.73M+6.3%6.76M4.35
Nov 14, 202527.7M+1.41M+5.4%6.60M4.20
Oct 31, 202526.3M+2.50M+10.5%5.78M4.55
Oct 15, 202523.8M−2.06M−8.0%7.96M2.99
Sep 30, 202525.8M+1.58M+6.5%6.03M4.29
Sep 15, 202524.3M−960.2K−3.8%6.06M4.01
Aug 29, 202525.2M+515.1K+2.1%5.34M4.73
Aug 15, 202524.7M−738.2K−2.9%5.64M4.38
Jul 31, 202525.4M+114.0K+0.5%6.58M3.87
Jul 15, 202525.3M−2.51M−9.0%7.25M3.49
Jun 30, 202527.8M−1.92M−6.5%6.42M4.34
Jun 13, 202529.8M+1.77M+6.3%4.64M6.42
May 30, 2025Split28.0M+13.8M+97.1%4.41M6.36
May 15, 202514.2M−477.1K−3.3%3.27M4.35
Apr 30, 202514.7M+233.9K+1.6%3.46M4.24
Apr 15, 202514.5M+229.3K+1.6%5.37M2.69
Mar 31, 202514.2M+491.6K+3.6%3.27M4.34
Mar 14, 202513.7M+78.4K+0.6%4.06M3.38
Feb 28, 202513.7M+134.4K+1.0%3.02M4.52
Feb 14, 202513.5M+359.5K+2.7%2.58M5.24
Jan 31, 202513.2M+912.2K+7.5%3.69M3.56
Jan 15, 202512.2M+191.8K+1.6%2.74M4.46
Dec 31, 202412.1M+746.0K+6.6%2.98M4.05
Dec 13, 202411.3M−727.4K−6.0%2.45M4.62
Nov 29, 202412.0M−747.7K−5.9%2.16M5.56
Nov 15, 202412.8M−483.6K−3.7%2.95M4.33
Oct 31, 202413.3M−596.4K−4.3%2.61M5.08

Fails-to-deliver

Shares that weren't delivered by the settlement date, from the SEC, for the last 30 dates with fails. The price is the previous day's closing price published by the SEC.

Fails-to-deliver in FAST by settlement date
Settlement dateSharesPriceValue
Oct 9, 2026743$50.49$37.5K
Oct 6, 202673$50.69$3.70K
Sep 23, 2026535$50.08$26.8K
Sep 21, 2026800$49.01$39.2K
Sep 11, 20269$49.01$441.09
Sep 1, 202639,403$49.31$1.94M
Aug 24, 2026200$51.26$10.3K
Aug 18, 202620,220$51.23$1.04M
Aug 17, 202644$51.02$2.24K
Aug 10, 2026445$51.84$23.1K
Aug 6, 202634,918$49.99$1.75M
Jul 29, 202682$48.10$3.94K
Jul 9, 2026215$46.51$10.0K
Jul 8, 2026583$47.11$27.5K
Jul 1, 2026367$48.03$17.6K
Jun 30, 2026499$47.40$23.7K
Jun 29, 20264,408$47.10$207.6K
Jun 26, 20264,581$46.92$214.9K
Jun 23, 2026165$46.12$7.61K
Jun 17, 20269,360$46.05$431.0K
Jun 12, 20268,872$46.39$411.6K
Jun 11, 2026171$46.03$7.87K
Jun 8, 2026182,266$46.79$8.53M
Jun 4, 20262,686$46.46$124.8K
May 28, 20264,483$44.82$200.9K
May 27, 20261,342$44.45$59.7K
May 13, 202626$43.32$1.13K
Apr 23, 202624,026$44.81$1.08M
Apr 17, 202676,671$44.72$3.43M
Apr 15, 20269$44.62$401.58

Daily short volume

Off-exchange short-sale volume, not short interest: shares sold short each day in trades reported to FINRA, for the last 30 trading days.

The short volume ratio isn't a sentiment gauge: market makers sell short to fill buy orders and to hedge, so short sales are usually about half of off-exchange volume.

Off-exchange short volume in FAST by trade date
Trade dateShort volumeShort exemptOff-exchange volumeShort volume ratio
Nov 11, 20261,032,8794,0151,456,97570.9%
Nov 10, 20261,025,7704,5181,983,46951.7%
Nov 9, 20261,165,9618,0072,917,22940.0%
Nov 6, 20261,170,4424301,837,41263.7%
Nov 5, 20262,587,5959,4424,066,53063.6%
Nov 4, 20262,338,6863,0074,139,45456.5%
Nov 3, 2026906,3593771,485,09261.0%
Nov 2, 20261,059,0365,4141,695,84562.4%
Oct 30, 20261,473,7666,3682,209,10266.7%
Oct 29, 20261,446,6862,9672,036,39671.0%
Oct 28, 2026837,5732,3881,515,88555.3%
Oct 27, 20261,028,0364,1371,712,97260.0%
Oct 26, 2026906,0852,3881,579,80157.4%
Oct 23, 20261,280,8172,9311,838,52369.7%
Oct 22, 20261,675,7691,2842,727,51161.4%
Oct 21, 20261,307,8163,9242,286,87557.2%
Oct 20, 20261,265,78213,1921,947,44865.0%
Oct 19, 20261,224,4771,2881,925,39863.6%
Oct 16, 20261,582,6903532,416,16165.5%
Oct 15, 20262,249,1993,3033,953,53456.9%
Oct 14, 20265,327,4855,1607,884,93767.6%
Oct 13, 20262,211,7213393,211,46168.9%
Oct 12, 20261,404,2708,9721,969,85071.3%
Oct 9, 20261,043,5314601,546,13267.5%
Oct 8, 20261,464,11714,8542,083,80370.3%
Oct 7, 20261,397,3752091,932,15172.3%
Oct 6, 2026918,7179,0941,350,97568.0%
Oct 5, 2026949,0416031,419,89566.8%
Oct 2, 20261,502,4951,7152,005,90474.9%
Oct 1, 20261,594,7844,0002,168,17673.6%

ATS (dark pool) volume

Weekly volume on alternative trading systems (ATS) and other off-exchange (OTC) venues, from FINRA, for the last 12 weeks. ATS share is ATS volume ÷ (ATS + OTC volume), not a share of all trading.

Weekly ATS and OTC volume in FAST
Week ofTierATS sharesATS tradesOther OTC sharesOther OTC tradesATS share
Oct 19, 2026T17,898,923123,1505,379,62036,51459.5%
Oct 12, 2026T114,242,680172,5879,138,06350,58560.9%
Oct 5, 2026T16,191,131100,6873,521,18431,80263.7%
Sep 28, 2026T16,366,253106,60111,940,06736,54334.8%
Sep 21, 2026T17,988,355116,4266,851,76533,84553.8%
Sep 14, 2026T15,971,424104,2755,834,44932,91750.6%
Sep 7, 2026T15,187,86875,6304,024,73424,51456.3%
Aug 31, 2026T16,747,291102,3135,723,23434,91554.1%
Aug 24, 2026T15,204,80394,7574,430,87231,43654.0%
Aug 17, 2026T15,627,57497,9834,707,32534,62754.5%
Aug 10, 2026T17,694,359114,3715,215,34333,84659.6%
Aug 3, 2026T19,265,489139,2796,609,96443,71758.4%