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 Pin Connector Block 1 x 5 x 3Light Bluish GrayPart 32333Element 6271360 or 4205761×2
Technic Brick 1 x 14 [13 Pin Holes]WhitePart 32018Element 4161723 or 4112515×2
Wheels and Tyres
8 pieces
Tyre 81.6 x 36 RBlackPart 56907Element 6241908 or 6022941×4
Wheel 56 x 34 Technic Racing Medium with 6 Pin HolesBlackPart 15038Element 6284703 or 6253256×4
Plates Round Curved and Dishes
7 pieces
Plate Round 2 x 2 with Rounded Bottom [Boat Stud]BlackPart 2654Element 4617551 or 4278359×1
Plate Round 1 x 1 with Solid StudTrans-ClearPart 6141Element 6514052 or 62400301 spare in the box×6
Tubes and Hoses
6 pieces
Hose, Ribbed 7mm D. 11L / 8.8cmFlat SilverPart 78c11Element 46174922 spares in the box×6
Bricks Curved
4 pieces
Brick Curved 10 x 1 [Asymmetric Inside Ridges]WhitePart 85970Element 4547368×2
Brick Curved 3 x 1 No StudsWhitePart 50950Element 6548268 or 4249112×2
Technic Special
4 pieces
Technic Linear Actuator Mini with Dark Bluish Gray Head and Orange AxleLight Bluish GrayPart 92693Element 6221464 or 4612100×3
Technic Changeover Catch - + openingRedPart 6641Element 6099696 or 4270473×1
Tiles
4 pieces
Tile 1 x 2 with GrooveWhitePart 3069bElement 6548264 or 306901×2
Tile 1 x 3WhitePart 63864Element 6552134 or 6548270×2
Stickers
2 pieces
Sticker Sheet 1 for Set 42000-1[No Color/Any Color]Part 13575Element 6030681×1
Sticker Sheet 2 for Set 42000-1[No Color/Any Color]Part 13576Element 6030682×1
Bricks Round and Cones
1 piece
Brick Round 2 x 2 with Axle HoleRedPart 3941Element 614321 or 394121×1
Tiles Round and Curved
1 piece
Tile Round 2 x 2 with Bottom CrossBlackPart 4150Element 415076 or 415026×1
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.