To effectively navigate this guide, it is recommended you take advantage of the search feature. To do this, press CTRL+F on your keyboard. This will bring up a search box, allowing you to quickly find what you're looking for.

An example search.

MR - Mastery Rank. Most items require you to achieve a certain mastery rank on a location to unlock them. You can increase your mastery rank by completing Challenges.

PRO - Professional Mode. These unlocks require you to achieve the maximum mastery rank on the Professional Difficulty Level.

ET - Elusive Target. These unlocks require you to complete any Elusive Target at the location.

ESC - Escalation. These unlocks require you to complete the highest level of an Escalation.

GOTY - Game of the Year. Some items may require you to own the Game of the Year edition to be eligible for unlock.

CLG - Challenge. These unlocks require you to complete a specific challenge.

These items are unlocked for use by default for all players to use.

• HWK21 Pistol
  
• ICA19 Pistol
  
• TAC-SMG
  
• Enram HV
  
• TAC-4 AR Auto
  
• Fiber Wire
  
• Lockpick
  
• Coin
  
• Modern Lethal Syringe
  
• ICA Proximity Explosive
  
• 47's Signature Suit

• MR5 - Jaeger 7 Sniper Rifle
  
• MR10 - ICA Silverballer Pistol
  
• MR11 - Sedative Poison Vial
  
• MR15 - TAC-SMG Suppressed
  
• MR20 - HWK21 Covert Pistol
  
• MR20 - ICA Remote Explosive
  
• PRO - Napoleon Blownaparte
  
• ET - Tuxedo w/Gloves
  
• ESC - The Corky Commotion - A New Bat (GOTY only)
  
  
  Holiday Hoarders
• CLG - St. 47 - Santa Suit

• MR5 - Remote Breaching Charge
  
• MR10 - ICA Remote Audio Distraction
  
• MR10 - Lethal Poison Vial
  
• MR15 - Enram HV Custom Shotgun
  
• MR20 - Jaeger 7 Lancer Sniper Rifle
  
• MR20 - Proximity Explosive Duck
  
• PRO - Antique Emetic Syringe
  
• ET - Italian Suit w/Gloves
  
• CLG - The Living Dead - Unlock Morgue Starting Location
  
• CLG - Master Sniper - Jaeger 7 Covert Sniper
  
• CLG - Plumber's Apprentice - Claw Hammer
  
  
  The Icon
• CLG - Mission Mastery - The Iconator
  
  
  Landslide
• CLG - Mission Mastery - The Big One
  
  
  The Author
• No Unlocks Available.

• MR5 - Combat Knife
  
• MR10 - ICA19 F/A Pistol
  
• MR10 - Emetic Poison Vial
  
• MR15 - Remote Explosive Duck
  
• MR20 - TAC4 AR Stealth Assault Rifle
  
• MR20 - Proximity CX Demo Block
  
• PRO - Crystal Ball
  
• ET - Summer Suit w/Gloves
  
• CLG - Floor It! - Unlock Consulate Parking Garage Starting Location
  
• CLG - Master Fortune Teller - TAC-4 AR Desert
  
  
  A House Built on Sand
• CLG - Mission Mastery - Jambiya
  
• ESC - Cheveyo Calibration - Sieger 300 Ghost (GOTY only)

• MR5 - Nna Obara's Machete
  
• MR10 - Suppressed Enram HV Shotgun
  
• MR10 - ICA Explosive Phone
  
• MR15 - Jaeger 7 "Tiger" Sniper Rifle
  
• MR20 - Krugermeier 2-2
  
• MR20 - Mixtape 47
  
• PRO - ICA19 F/A Stealth Pistol
  
• ET - Casual Suit w/Gloves
  
• CLG - Tuppence A Wish - Gold Coin
  
• CLG - Himmapan Horror - Antique Lethal Syringe
  
  
  The Source
• No Unlocks Available.

• MR5 - Modern Emetic Syringe
  
• MR10 - RS-15 Assault Rifle
  
• MR10 - Concealable Baton
  
• MR15 - Disposable Scrambler
  
• MR20 - TAC-4 S/A Semi-Auto Rifle
  
• MR20 - Remote CX Demo Block
  
• PRO - Sieger 300 Advanced Sniper Rifle
  
• ET - Tactical Gear with Hunter's Hat
  
• CLG - King of the Crop - TAC-4 SA Jungle
  
  
  The Vector
• No Unlocks Available.

• MR5 - Custom 5mm Pistol
  
• MR7 - Shuriken
  
• MR10 - Okinawan Tonfa
  
• MR15 - Explosive Compound
  
• MR20 - Concealable Knife
  
• MR20 - Sieger 300 Sniper Rifle
  
• MR20 - Unlocked Loadout Slots
  
• PRO - HF Championship Bat
  
• ET - White Yukata (robe)
  
• CLG - The Art of Revenge - Masamune (katana)
  
• ESC - The Dexter Discordance - Striker Pistol (GOTY only)

• Complete any 10 escalations - TAC-SMG Covert

• Complete 5 ET’s with any ranking - Absolution Suit w/gloves
  
• Complete 10 ET’s with any ranking - Blood Money Suit w/gloves
  
• Complete 13 ET’s with any ranking - Signature Suit w/gloves
  
• Complete 1 ET with Silent Assassin ranking - Terminus Suit
  
• Complete 5 ET’s with Silent Assassin ranking - Winter Suit

All items in this section will be automatically unlocked if you own the requisite DLC.

• Corky The Clown
  
• Cowboy Suit
  
• Raven Suit
  
  
  Requiem Pack Content
• Requiem Suit
  
• The Pale Duck
  
• ICA Chrome

The original source for this information was /u/Left4DayZ1 on Reddit. Give him thanks here: https://www.reddit.com/r/HiTMAN/comments/7rahqz/here_is_a_full_list_of_unlockables/

If you notice any error or omission in this guide, please let me know. Any errors will swiftly be rectified and you'll get a mention here!