In Borderlands 4, the developers have prepared several vaults for players scattered across the planet Kairos. There are four in total, and while the Vault Timekeeper is tied to the main storyline, the other three are completely optional but intriguing, especially if you want to explore all the game content.

To open a vault, you need to collect three vault key fragments hidden in the region where it is located. Each of the main zones—The Fadefields, Carcadia Burn, and Terminus Range—contains three fragments. This guide will help you find all the vault key fragments in Borderlands 4 so you can unlock all Primordial Vaults and claim your rewards.

What are Vault Key Fragments in Borderlands 4

Each vault key is divided into three fragments scattered throughout the respective region. To make the search easier, you can activate the nearest Order SILOs. They unlock fast travel points, provide SDU credits, and mark the search area for each fragment. While using SILOs is not mandatory, they offer convenient landmarks for finding key fragments.

Why Collect Vault Key Fragments in Borderlands 4

Each vault in Borderlands 4 gives you access to legendary items, including powerful weapons and unique cosmetic items, which you will receive after clearing these vaults. However, to access these vaults, you need the keys to them. Of course, this is not a mandatory activity in Borderlands 4, but it's a great way to stock up on valuable items.

Order Silos will help you find your way to key fragments and unlock fast travel points and additional resources, so it's worth activating them even when you already know the exact location of the fragment.

For completionists and true vault hunters, searching for these fragments is one of the most exciting aspects of exploring Kairos and the game as a whole.

All Vault Key Fragment Locations in The Fadefields

The Fadefields will be the first game area you explore in Borderlands 4. It is a spacious and diverse landscape filled with Order patrols, butcher camps, and strange biomes. Although a significant part of the story takes place here, you are free to search for vault key fragments as soon as you arrive.

Where to Find the Vault Key Fragment in Coastal Bonescape

Using The Stockroom SILO, you will receive a marker leading you to Stillshore on the western coast. The fragment lies on a wooden crate on the first floor of a house by the seaside. It's very easy to obtain once you reach this location.

Where to Find the Vault Key Fragment in The Howl

Head to the rock formations in The Howl location. Inside the cave, you will see the fragment on a pillar, surrounded by rocks with golden veins.

Where to Find the Vault Key Fragment in Dissected Plateau

Deep Seven SILO will lead you to the area of Rosemary’s Reserve. Look for a blocked ventilation shaft that can be opened with a hook. Inside, next to a couple of corpses and a figurine on an idol tank, you'll find the third key fragment of The Fadefields in Borderlands 4.

The Fadefields Vault Door

Once you gather all three fragments, head to the hill east of Zaldra’s Backup Plan. Fight your way through the wreckage of a destroyed ship until you reach the vault door. Insert the fragments into the receiver, and the door will open.

Vault Key Fragment Locations in Carcadia Burn

Carcadia Burn is a desert land where you encounter familiar characters and new dangers. Like in The Fadefields, the vault key fragments here are easy to obtain, but you'll still have to fight through enemy camps and Order blockades.

Where to Find the Vault Key Fragment in Lopside

For convenience, you can open the Rustic Hurl SILO or head straight to the Makeshift Chalet Safehouse. From there, head south to Lopside and find an abandoned gas station with a faded "One Pumper" sign. Climb or hook your way to the roof, and you'll find the fragment on the dining table.

Where to Find the Vault Key Fragment in Ruined Sumplands

Judgement’s Lapse SILO points to the Hull’s Handbasket location, where the key fragment is located along the waterline. Descend from the cliff near the northern bridge to the shallow waters. The fragment lies between rocks, on a pillar.

Where to Find the Vault Key Fragment in Tonnage Peel

Site Unseen SILO will guide you to the wreck of the Last Great Hope. The fragment is hidden under the ship's debris and is accessible only after you open the ventilation doors inside the hull. Follow the flickering red lights to find it.

Carcadia Burn Vault Door

After collecting all three fragments, head northwest of The Rustical Hurl SILO. The vault is located near a bridge, among a pile of scrapped cars, on the edge of a cliff.

Vault Key Fragment Locations in Terminus Range

The snowy mountains of Terminus Range hide the final, third vault. This area is a complex network of rocks and caves, where enemy outposts can pose a serious obstacle in your search.

Where to Find the Vault Key Fragment in Cuspid Climb

Activating the Reliquary SILO will direct you to a point with a hot air balloon that will help you fly to a stone bridge near a waterfall. In the cave beyond, among the battle remnants and two bodies, the first key fragment awaits you.

Where to Find the Vault Key Fragment in The Low Leys

In The Low Leys, head to The Pit. On the road, look for a dead tree with purple petals below. Climb the rocky ledges to the northeast, then even higher using a hook. The fragment is located at the top.

Where to Find the Vault Key Fragment in Windspear

The next vault key fragment in Borderlands 4 is located near the border between Windspear and The Low Leys, near Checkpoint Taupe and Vestal Garrison. Enter the Order base from the south side, clear the way of enemies, and climb to the office on the second floor. There, the fragment lies on a crate under a large monitor.

Terminus Range Vault Door

The vault can be found south of the fragment location in Checkpoint Taupe. Look for the cave entrance above Mangler’s lair by the road. Insert all the fragments, and the final Primordial vault will open.