Tiers are used to categorize all items in Astroneer. Tiers exist based on whether the item fits in a certain attachment slot or based on which Printer the item is crafted from, such as Titanium and a stack of Tethers being Tier 1, or Research Items and Medium Wind Turbines being Tier 2. Items that are in Crates, such as freshly printed items or those packed with a Packager, are considered one tier lower than when they are unpacked. For instance, a packed Medium Printer (Tier 2) fits in a Tier 1 attachment slot, and a packed Extra Large Shredder (Tier 4) fits in a Tier 3 attachment slot.
Tier 1 refers to any small-sized item. Items in this category fit into a single slot and can be dragged around easily. These items are small enough to be stored in the Backpack, and include Resources or any item crafted in the Backpack Printer. A select few items can also be printed in the Small Printer. Some items, such as the Small Solar Panel, spawn a Small Platform when placed on the ground. This allows the item to be used without it being placed in an attachment slot.
Tier 2 refers to any medium-sized item. Items in this category fit onto a 2-slot connection and must be placed on a platform if they require power to function. This tier includes all Research Items as well as all items that can only be crafted with a Small Printer, e.g., the Medium Storage. These items cannot be placed in the backpack, but the player may instead carry one of them by selecting the item and dragging it into their hands or by pressing the Use key (default F, or for keyboard, Xbox, and PS4 respectively). Holding the item will slow the player down until they drop the item. Medium items may be packaged with a Packager so they may be placed in the backpack.
Tier 3 refers to any large-sized item. Items in this category fit onto a 4-slot connection and must be placed on a platform if they require power to function. These items cannot be easily carried, and the player moves much slower when holding them. Packaging these items with a Packager makes them Tier 2, allowing easier transport. Items in this tier include Research Chamber, Medium Rover, and any other item crafted at the Medium Printer.
Tier 4 refers to extra large-sized items. Items in this category fit onto an 8-slot connection and modules must be placed on a platform if they require power to function. These items are hardest to move, making the player stand still when being held, requiring being in a Crate to allow the player to move. This tier includes Large Rovers, Shuttles, and any other item made in the Large Printer. Tier-4 items can’t be shredded and need to be blown up with Dynamite to be broken down into shreddable debris.
- In SES Vlog 23, a Rover with an unreleased tier of Attachment Slot was shown, which looked like a fifth tier. This never actually made it into the game, and was described as a "wild exploration".
Unreleased tier of Attachment Slot shown in SES Vlog 23.