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.
LEGO counts 1,368 pieces. This inventory comes from a separate parts catalog and lists 1,366; the two do not always count the same elements, so their totals differ. Spare parts are counted in neither figure.
Before you call it missing
Builders who report a missing piece often find it in one of these places. Tick each one off as you look.
Motor Pulley, 9V Micromotor with axle holeLight GrayPart 2983Element 298630×1
Motor, 9V 5 x 4 x 2 1/3, Dark Gray BottomLight GrayPart 2838c01Element 4494210 or 74569×1
Pole Reverser / Polarity Switch with Center Part [Complete Assembly]Light GrayPart 6551c01Element 75214×2
Motor Cover, 9V Micromotor 2 x 2 BaseRedPart 2985Element 4109830 or 298521×2
Motor, 9V Micromotor 2 x 2RedPart 2986Element 70823×1
Cable, Fiber OpticsTrans-ClearPart 6640Element 4109999 or 664040×8
Battery Box, 9V 4 x 14 x 4 with Dark Gray Base [Complete Assembly]WhitePart 2847c01Element 4109815 or 4100352×1
Wheels and Tyres
19 pieces
Tyre Offset Tread 24 x 8BlackPart 3483Element 4501048 or 348326×6
Technic Wedge Belt Wheel [aka Pulley]Light GrayPart 4185Element 4100502 or 418502×5
Wheel with Split Axle holeWhitePart 3482Element 4279395 or 4194244×6
Technic Wedge Belt Wheel [aka Pulley]YellowPart 4185Element 6636439 or 6363273×2
Plates Wedged
13 pieces
Wedge Plate 3 x 3 Cut CornerBlackPart 2450Element 4227684 or 245026×4
Wedge Plate 3 x 6 Cut CornersBlackPart 2419Element 241926×3
Wedge Plate 3 x 3 Cut CornerWhitePart 2450Element 6601842 or 4280148×2
Wedge Plate 3 x 4 without Stud NotchesWhitePart 4859Element 4215973 or 4199395×2
Wedge Plate 3 x 6 Cut CornersWhitePart 2419Element 6552090 or 241901×2
Bricks Wedged
11 pieces
Brick Wedged 3 x 4 [No Stud Notches]BlackPart 2399Element 4189285 or 239926×1
Brick Wedged, Angled 3 x 2 LeftBlackPart 6565Element 4527766 or 656526×1
Brick Wedged, Angled 3 x 2 RightBlackPart 6564Element 4526931 or 656426×1
Brick Wedged, Angled 3 x 2 LeftWhitePart 6565Element 4527764 or 656501×3
Brick Wedged, Angled 3 x 2 RightWhitePart 6564Element 4526928 or 656401×3
Brick Wedged, Sloped 4 x 4 Triple, No Stud NotchesWhitePart 6069Element 4184152 or 606901×2
String, Bands and Reels
9 pieces
Technic Rubber Belt Medium [24mm ID] [Round Cross Section]RedPart 85544Element 4544145 or 4544143×7
Rubber Belt Small [15mm ID] [Round Cross Section]WhitePart 85543Element 6699001 or 45806651 spare in the box×2
Plates Round Curved and Dishes
5 pieces
Plate Round 1 x 1 with Solid StudBlackPart 6141Element 6141261 spare in the box×4
Plate Round 2 x 2 with Axle Hole Type 1 (+ Opening)Light GrayPart 4032aElement 403202×1
Technic Steering, Suspension and Engine
5 pieces
Technic Engine CrankshaftLight GrayPart 2853Element 4119475 or 285302×4
Technic Shock Absorber 6.5L with Normal Spring [Complete Assembly]Light GrayPart 73129Element 73129×1
Bricks
4 pieces
Brick 1 x 8BlackPart 3008Element 300826×2
Brick 1 x 2 x 5 with Blocked Open Studs and Bottom Stud Holder with Asymmetric RidgesWhitePart 2454a×2
Panels
4 pieces
Panel 1 x 2 x 1 [Square Corners]BlackPart 4865aElement 486526×2
Panel 1 x 2 x 2 [Solid Studs]WhitePart 4864aElement 4113016 or 486401×2
Bricks Round and Cones
3 pieces
Brick Round 2 x 2 with Axle HoleLight GrayPart 3941Element 614302 or 394102×1
Brick Round 2 x 2 with Axle HoleWhitePart 3941Element 6601920 or 614351×2
Tiles Round and Curved
3 pieces
Tile Round 2 x 2 with Bottom CrossLight GrayPart 4150Element 415052 or 415002×1
Tile Round 2 x 2 with Bottom CrossWhitePart 4150Element 415051 or 415001×2
Transportation - Sea and Air
3 pieces
Propeller HousingBlackPart 6040Element 4144525 or 604026×3
Plants & Trees
2 pieces
Plant, Palm Tree Trunk - Short Connector, Axle Hole with 2 Inside ProngsBlackPart 6135Element 613526×2
Transportation - Land
2 pieces
Seat / Chair 2 x 2YellowPart 4079×2
Stickers
1 piece
Sticker Sheet for Set 8480-1[No Color/Any Color]Part 71320Element 4100356×1
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.