Here is the full list of all 40 Bitardia achievements.
The base game contains 37 achievements, and there is 1 DLC pack containing 3 achievements.
Finish the "Fifth Column" quest
Get arrested for spoiling the stand
Get to jail while taking the camera
Get to jail after talking to police
Served a term in prison
Finish the "Fifth wheel" quest
Finish the "Missing part" quest
Finish a halloween-quests
Beat anon in cards
Finish the "Hotline Bitardia" quest
More than 100 killed on arena
Get some cash on arena
Finish the "QT 3.14" quest
Buy a pillow for anon
Rob the caravan
Take care of the hospital
Take care of the bank
Return anon's debt
Finish the "Winter is coming" quest
Agree to work on Abu
To die, refusing to work on the Abu
Break out of prison
Get to jail after showing the video
Rescue the hostage
Get to jail after entering the police station
Explode the building
Kill anons on the first mission
Kill cancer on the first mission
Take the builder quest
You have finished the note-finding mission
You didn't accept the note-finding mission
Take the guard quest
Kill Cancer on the first mission
Pick Anon Mask
Pick Cancer Mask
Agree to work for resistance