| ChangEdFintech | Fintech | Chicago, United States | Nick Martini | gochanged.com |
| Channel3B2B | B2B | New York, United States | | trychannel3.com |
| CharB2B | B2B | — | John Jeong | char.com |
| Charlie HRB2B | B2B | — | Ben Gateley | charliehr.com |
| Charm IndustrialIndustrials | Industrials | — | Peter Reinhardt | charmindustrial.com |
| Charter SpaceOther | Other | London, United Kingdom | — | charter.space |
| ChasiB2B | B2B | — | | chasi.co |
| ChassyB2B | B2B | Renton, United States | — | chassy.io |
| ChecklyB2B | B2B | — | Tim Nolet | checklyhq.com |
| CheerfyOther | Other | London, United Kingdom | — | cheerfy.com |
| Chestnut FortyConsumer | Consumer | — | Veniamin Veselovsky | chestnutforty.com |
| Chi AIB2B | B2B | Alpharetta, United States | — | thechi.app |
| chowboticsOther | Other | Redwood City, United States | Deepak Sekar | chowbotics.com |
| ChronosphereB2B | B2B | — | Martin Mao | chronosphere.io |
| CiaoConsumer | Consumer | — | — | meetciao.com |
| CICLA 3DOther | Other | Tampa, United States | — | cicla3dshop.com |
| CinchyB2B | B2B | Toronto, Canada | Dan DeMers | cinchy.com |
| CIPRA.aiOther | Other | San Diego, United States | — | cipra.ai |
| Circa LabsFintech | Fintech | Bridgeport, United States | — | wearecirca.com |
| CircuitOther | Other | Huntingdon, United Kingdom | Hal Watts | getcircuit.com |
| CircularPlaceIndustrials | Industrials | Meudon, France | — | circularplace.fr |
| CISGAMOther | Other | Cerritos, United States | — | cisgam.com |
| Citrus OncologyOther | Other | Cary, United States | — | citrusoncology.com |
| CitruslabsIndustrials | Industrials | Santa Monica, United States | Nora Abousteit | citruslabs.com |
| CityCopOther | Other | San Francisco, United States | — | citycop.org |
| Civic EagleOther | Other | Mounds View, United States | Damola Ogundipe | civiceagle.com |
| CivilGridB2B | B2B | United States | — | civilgrid.com |
| ckbkConsumer | Consumer | London, United Kingdom | Matthew Cockerill | ckbk.com |
| Clad LabsConsumer | Consumer | San Francisco, United States | | cladlabs.ai |
| ClaimGlideHealthcare | Healthcare | — | | claimglide.com |
| ClamB2B | B2B | — | | tryclam.com |
| ClaraHealthcare | Healthcare | San Francisco, United States | Zeeshan Ahmed | askclara.com |
| ClaraB2B | B2B | Abu Dhabi, United Arab Emirates | Gus Cerro | clara.co |
| ClarisightsOther | Other | Palo Alto, United States | Avinash Kunnath | clarisights.com |
| ClaroAIOther | Other | Hod HaSharon, Israel | — | claroai.com |
| ClassPassIndustrials | Industrials | New York City, United States | Payal Kadakia | classpass.com |
| ClassWalletFintech | Fintech | Miami, United States | Jamie Rosenberg | classwallet.com |
| ClayB2B | B2B | — | Kareem Amin | clay.run |
| ClaybirdB2B | B2B | San Francisco, United States | Saad Jamal | claybird.com |
| Clean OSHealthcare | Healthcare | Milan, Italy | — | thecleanos.com |
| Clear Solar CorporationIndustrials | Industrials | Hurley, United States | — | clearsolarco.com |
| ClearbitB2B | B2B | — | Alex MacCaw | clearbit.com |
| ClearstepOther | Other | Chicago, United States | Adeel Malik | clearstep.health |
| CledaraFintech | Fintech | London, United Kingdom | Cristina Vila | cledara.com |
| CleoFintech | Fintech | — | Barney Hussey-Yeo | meetcleo.com |
| CleonB2B | B2B | New York, United States | | getcleon.ai |
| CleverPetB2B | B2B | La Jolla, United States | Leo Trottier | clever.pet |
| ClickHouseB2B | B2B | — | Alexey Milovidov | clickhouse.com |
| ClicksB2B | B2B | San Francisco, United States | | goclicks.ai |
| ClicktivatedOther | Other | Birmingham, United States | Jason Shroot | clicktivated.com |