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.
Scala Baby with Small Blue Eyes Print (Thomas)NougatPart scafig0013pr0002×1
Stickers
1 piece
Sticker Sheet for Set 3152-1[No Color/Any Color]Part 22958Element 4141451×1
Technic Steering, Suspension and Engine
1 piece
Technic Steering Wheel Small (3 Studs Diameter)OrangePart 2819Element 4141534×1
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.