| Year | Title | Role | Notes |
| 2004 | Joey | Molly | Episode: "Joey and the Party" |
| 2005 | The Comeback | Sales Girl | Episode: "Valerie Demands Dignity" |
| Six Feet Under | Donna | Episode: "The Rainbow of Her Reasons" |
| Stacked | Brenda | Episode: "Nobody Says I Love You" |
| 2005, 2013 | How I Met Your Mother | Coat Check Girl | 2 episodes |
| 2006 | If You Lived Here, You'd Be Home Now | Sandra | Pilot (unaired) |
| 30 Even Scarier Movie Moments | Herself | Miniseries |
| House | Hannah | Episode: "Sleeping Dogs Lie" |
| Studio 60 on the Sunset Strip | Daphne | Episode: "Pilot" |
| Entourage | Jen | Episode: "Sorry, Ari" |
| 2006–2010 | Heroes | Charlie Andrews | Recurring role; 5 episodes |
| 2007 | Nice Girls Don't Get the Corner Office | Angela | Pilot (unaired) |
| 2007–2008 | Ugly Betty | Charlie | Recurring role; 8 episodes |
| 2007 | Ghost Whisperer | Jennifer Billings | Episode: "The Underneath" |
| Pushing Daisies | Elsita / Elsa | Episode: "Pigeon" |
| 2008–2019 | Drunk History | Annabelle / Abigail Adams / Marjory Stoneman Douglas / Florence Schaffner | Recurring role; 4 episodes |
| 2008 | Back to You | Shelley Ken | Episode: "Date Night" |
| 2009–2015 | Glee | Emma Pillsbury | Main role (seasons 1–3); recurring (season 4–6) |
| 2012–2014 | The League | Trixie Von Stein | Recurring role; 6 episodes |
| 2013 | NTSF:SD:SUV:: | Clock | Episode: "The Great Train Stoppery" |
| 2013–2015 | The Millers | Debbie | Main role; 34 episodes |
| 2014–2015 | Getting On | Suzi Sasso | 5 episodes |
| 2015–2018 | The Adventures of Puss in Boots | Dulcinea | Voice; Main role |
| 2015 | Resident Advisors | Michaela Roberts | Episode: "Motivational Speaker" |
| 2015 | Wet Hot American Summer: First Day of Camp | Jessica | 2 episodes |
| 2015 | Gigi Does It | | Episode: "Love Thyself" |
| 2017–2018 | Trial & Error | Carol Anne Keane | Main role |
| 2018 | Great News | Cat | Episode: "Catfight" |
| 2022 | United States of Al | Cindy | 6 episodes |
| 2025 | Leanne | Mary | 10 episodes |