Rule out the usual hiding places first. If the piece really is gone, check the set piece by piece
and leave with the element ID LEGO asks for, or a link to buy the part.
Technic Brick 1 x 1 with Axle HoleSand GreenPart 73230Element 6359069×2
Technic Brick 1 x 1 with Pin HoleYellowPart 6541Element 654124×2
Transportation - Land
2 pieces
Wheel Arch, Mudguard 2 x 3 x 1 1/3 with 2 x 2 PlateTanPart 49097Element 6397562×2
Windows and Doors
2 pieces
Door Frame 1 x 4 x 6 Type 2TanPart 60596Element 6262949 or 4578110×1
Glass for Window 1 x 4 x 6 with Gold Mandarin on Red Background, Gold Border PrintTanPart 57895pr0030Element 6465555×1
Minifig Heads
1 piece
Minifig Head [Plain] [Vented Stud - 2 Holes]BluePart 28621Element 6454717×1
Minifig Headwear
1 piece
Helmet Round Sphere with Small HoleOpal Trans-Light BluePart 51283Element 6514316 or 6324167×1
Minifig Upper Body
1 piece
Torso Mechanical, Battle DroidTanPart 30375Element 4262538 or 4143659×1
Tools
1 piece
Brick and Axle Separator v2.0OrangePart 96874Element 6240515 or 4654448×1
Tick each piece as you find it, or mark it missing.
When a piece really is missing
Ask LEGO
LEGO takes requests for pieces missing from a new set through its customer service site. The form asks for
the set number and each piece's element ID, the number printed beside the piece in the parts list at the back
of the instructions. This checker lists both.
Mark a piece missing and your list links it to an eBay search for that part, which also covers pieces from
older or second-hand sets.
Keep a record
Copy or download your missing list (the CSV opens in any spreadsheet), or print the whole checklist and tick
pieces off on paper. Your marks stay in this browser, so you can check a big set over several sittings.