|“||Friends don't let friends sneak into insane asylums alone.||”|
— Aria to Hanna
Hanna and Aria are very close from the beginning. When Aria broke up with Ezra, Hanna visited Ezra at Hollis College and told him that two people who love each other that much should be together, and when Caleb broke up with Hanna, she cried in Aria's lap as she tried to comfort her. Aria was the one who recommended Hanna talk to Caleb about "A". Aria doesn't let Hanna sneak into Radley by herself as she quotes: "Friends don't let friends sneak into insane asylums alone". Then, Hanna stays at Aria's house as Ashley is not home. Aria is also the first to know about Hanna telling to Mrs DiLaurentis that Alison is still alive. After Caleb was shot, Hanna hugs Aria as Aria rubs her arm and tells her it's going to be ok. When Hanna, Aria, Emily, and Spencer are at the hospital as Caleb was hurt, Aria hugs Hanna. Hanna was the first person Aria told about Ezra's kid and Maggie. Then, Hanna suggests Aria should tell Ezra about his son because secrets tear people apart. When Aria found out about Jackie, Hanna supports her and tells her: "Fool me once, shame on you, fool my best friend and you are dead freaking meat." It is shown that Hanna cares deeply for Aria because in She's Come Undone, Hanna stays with Aria, being nice to her and not wanting to leave her on her own.
- Aria was the only one who told Alison to stop being mean to Hanna when they were younger.
- Hanna is the first one to find out about Aria and Ezra's relationship.
- Aria was the only one who went to Radley to visit Mona in order to help Hanna.
- Lucy Hale and Ashley Benson have been best friends since they were 15 years old.
Aria [in The Perfect Storm]: I'm not looking for anyone more than a friend.
Hanna: Why? I mean, don't you already have enough on Facebook?
Aria [in Keep Your Friends Close]: Are you sure you gonna be okay?
Hanna: Aria, I went to fat camp for five summers. I can handle some woods.
Aria [in Know your Frenemies]: A saved my relationship...
Hanna: Yeah, well A tried to kill me.
Hanna [in Je Suis Une Amie]: Go Emily!
Aria: She's not swimming yet...
Caleb [in Monsters in the End]: Listen, I don't know what Hanna told you, but -
Aria: Everything, we're best friends.
Hanna [to Aria in Monsters in the End]: Fool me once? Shame on you. Fool my best friend? You're dead freakin' meat.
Hanna [in Someone To Watch Over Me]: It's symbolic. Of our first night together. We... Heard owls.
Aria: Swooping down to carry off their prey?
Hanna [in Birds of a Feather]: You know what they say: if the feather fits.
Aria: Hanna, it's the shoe, if the shoe fits.
Hanna [in Birds of a Feather]: Why are you looking at pictures of bald fat men?
Aria: I'm looking for a guy for my mom. I don't know I just thought that she could try online dating.
Aria [in Crazy]: Hanna, friends don't let friends sneak into insane asylums alone.
Aria [in Scream for Me]: You're the problem, Hanna! You're always the problem!