| LabboxEducation | Education | Prishtina, Kosovo | — | labbox.education |
| LabbyOther | Other | Cambridge, United States | — | labbyinc.com |
| Lactation LabOther | Other | Santa Monica, United States | Stephanie Canale | lactationlab.com |
| LagoonFintech | Fintech | Tel Aviv, Israel | — | data-lagoon.com |
| LaiblOther | Other | Halifax, Canada | — | laibl.co |
| LandngB2B | B2B | Honolulu, United States | — | landng.com |
| LaneOther | Other | Toronto, Canada | Clinton Robinson | joinlane.com |
| LatchOther | Other | New York City, United States | Luke Schoenfelder | latch.com |
| Latimer ControlsB2B | B2B | Boulder, United States | — | latimercontrols.com |
| Latitudo40Industrials | Industrials | Naples, Italy | Alessio Traficante | latitudo40.com |
| Lauretta.ioB2B | B2B | Singapore, Singapore | — | lauretta.io |
| LawnStarterConsumer | Consumer | Austin, United States | Ryan Farley | lawnstarter.com |
| LayUp TechnologiesFintech | Fintech | Johannesburg, South Africa | Lethiwe Dube | layup.co.za |
| Lean Startup MachineB2B | B2B | San Francisco, United States | Trevor Owens | javelin.com |
| LeanplumOther | Other | San Francisco, United States | Momchil Kyurkchiev | leanplum.com |
| LearnPlatformOther | Other | Raleigh, United States | Ed Brophy | learnplatform.com |
| Legaleaze TechnologiesOther | Other | San Francisco, United States | — | legaleaze.co |
| LegalPadB2B | B2B | Seattle, United States | Tahmina Watson | legalpad.io |
| LegitFitFintech | Fintech | Cork, Ireland | — | legitfit.com |
| Lena HealthB2B | B2B | Houston, United States | — | lena.io |
| LendAPIFintech | Fintech | Orange, United States | Victor Cheng | lendapi.com |
| LendKoiFintech | Fintech | Sunrise, United States | — | lendkoi.com |
| LendorseFintech | Fintech | Munich, Germany | — | lendorse.com |
| LeOOther | Other | Tel Aviv, Israel | — | meetleo.co |
| Let's EnhanceB2B | B2B | Kyiv, Ukraine | Alex Savsunenko | letsenhance.io |
| LeucineB2B | B2B | Koramangala 7th Block, India | Rahul Gonuguntla | leucinetech.com |
| Level2Fintech | Fintech | Cardiff, United Kingdom | — | trylevel2.com |
| LevelTen EnergyIndustrials | Industrials | Seattle, United States | Bryce Smith | leveltenenergy.com |
| Lifebit BiotechOther | Other | London, United Kingdom | Maria Chatzou Dunford | lifebit.ai |
| LightboxB2B | B2B | San Mateo, United States | — | ninesixteen.com |
| Lightning Social VenturesFintech | Fintech | London, United Kingdom | — | lightningreach.org |
| LightstreamOther | Other | Chicago, United States | — | golightstream.com |
| LightwingB2B | B2B | Bengaluru, India | Aurélie Hélouis | lightwing.io |
| LineSightOther | Other | Oak Brook, United States | — | linesight-ai.com |
| Lingco Language LabsEducation | Education | Lansing, United States | Robert Sherwood | lingco.io |
| LingvistB2B | B2B | Tallinn, Estonia | Mait Müntel | lingvist.com |
| LinkBycarB2B | B2B | Paris, France | — | linkbycar.com |
| Linker FinanceFintech | Fintech | Pasadena, United States | — | linkerfinance.com |
| LinqAlphaOther | Other | Cambridge, United States | — | linqalpha.com |
| LipefiFintech | Fintech | Elsene, Belgium | — | lipefi.com |
| LiquidOther | Other | Los Angeles, United States | — | goliquid.io |
| Liquid DiamondsFintech | Fintech | New York City, United States | — | liquid.diamonds |
| LISNRB2B | B2B | Cincinnati, United States | Rodney Williams | lisnr.com |
| LiteStackFintech | Fintech | San Antonio, United States | — | zerovm.org |
| LitographsOther | Other | Cambridge, United States | James Dowd | litographs.com |
| LivOther | Other | San Francisco, United States | — | liv.tv |
| LiveLikeConsumer | Consumer | New York City, United States | Miheer Walavalkar | livelikevr.com |
| Liveoak TechnologiesB2B | B2B | Austin, United States | Will Thompkins | liveoak.net |
| Livsn DesignsOther | Other | Fayetteville, United States | Eric Browne | livsndesigns.com |
| Lo BioHealthcare | Healthcare | Rockville, United States | — | lo-bio.com |