Lyndsy Marie Fonseca (born January 7, 1987) is an American actress.
She is married to actor Noah Bean and they have one child.
- The Young and the Restless (2001–2005) as Colleen Carlton
- Boston Public (2003) as Jenn Cardell
- Malcolm in the Middle (2004) as Olivia
- NYPD Blue (2004) as Madison Bernstein
- How I Met Your Mother (2005–2014)note as Penny Mosby
- Big Love (2006–2009) as Donna
- Phil of the Future (2006) as Kristy
- CSI (2007) as Megan Cooper
- House (2007) as Addie
- Heroes (2007) as April
- Desperate Housewives (2007–2009) as Dylan Mayfair
- Nikita (2010–2013) as Alexandra "Alex" Udinov
- Agent Carter (2015–2016) as Angie Martinelli
- 9-1-1: Lone Star (2020-present) as Iris Blake
- Next Stop, Christmas (2021) as Angie Reynolds
- Kick-Ass (2010) as Katie Deauxma
- Hot Tub Time Machine (2010) as Jenny Steadmeyer
- The Ward (2010) as Iris
- Kick-Ass 2 (2013) as Katie Deauxma
- Aloof Dark-Haired Girl: Her most common roles are either a Deadpan Snarker or a straight-out Ice Queen. Sometimes both.
- But Not Too Foreign: Her father is of Portuguese descent, and her mother is of half Portuguese ancestry.
- Former Child Star: Downplayed, if not subverted. Not only did she started as a teenager (13), but she also has regular work.
- Playing Against Type: Her character in Agent Carter is far from her usual Aloof Dark-Haired Girl gigs.
- Spell My Name with an S: It is indeed spelled "Lyndsy", not the more traditional "Lyndsey".
- Typecasting: She's usually cast as an Aloof Dark-Haired Girl (see above). Very much averted in Agent Carter.