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LEGO Missing Piece Checker

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.

Flatiron Building

Checking

21023 Flatiron Building

471 pieces in 52 part and color combinations.

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.

Look-alike colors in this set

These parts appear in this set in two colors that are easy to confuse. If you are one short in one color, check whether it went in where the other color belongs. Each color has its own element ID in the parts list at the back of the instructions.

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Piece checklist

Tan 215 pieces

  • Brick 1 x 1 Tan Part 3005 Element 4113915 or 300505 ×5
  • Brick 1 x 2 Tan Part 3004 Element 4109995 or 300405 ×18
  • Brick 1 x 3 Tan Part 3622 Element 4162465 or 4113920 ×6
  • Brick 1 x 6 Tan Part 3009 Element 4112982 or 300905 ×4
  • Brick 2 x 2 Corner Tan Part 2357 Element 4124455 or 4112541 ×8
  • Brick Curved 2 x 1 No Studs [1/2 Bow] Tan Part 11477 Element 6046922 Also in Dark Tan ×12
  • Brick Curved 2 x 2 x 2/3 Tan Part 15068 Element 6046924 ×20
  • Brick Sloped 30° 1 x 1 x 2/3 (Cheese Slope) Tan Part 54200 Element 4516055 or 4278069 1 spare in the box ×9
  • Brick Special 1 x 2 with 2 Studs on 1 Side Tan Part 11211 Element 6024495 ×4
  • Plate 1 x 1 Tan Part 3024 Element 4159553 or 302405 1 spare in the box Also in Dark Tan ×3
  • Plate 1 x 2 Tan Part 3023 Element 4113917 or 302305 Also in Dark Tan ×21
  • Plate 1 x 3 Tan Part 3623 Element 4121921 or 362305 ×10
  • Plate 1 x 4 Tan Part 3710 Element 4113233 or 371005 Also in Dark Tan ×4
  • Plate 1 x 6 Tan Part 3666 Element 4124067 or 366605 ×3
  • Plate Round 1 x 1 with Solid Stud Tan Part 6141 Element 4161734 or 614105 1 spare in the box ×2
  • Tile 1 x 1 with Groove Tan Part 3070b Element 4125253 1 spare in the box Also in Dark Tan ×21
  • Tile 1 x 2 with Groove Tan Part 3069b Element 4114026 Also in Dark Tan ×20
  • Tile Special 1 x 2 Grille with Bottom Groove Tan Part 2412b Element 4124456 or 393305 ×45

Dark Tan 109 pieces

  • Brick Curved 2 x 1 No Studs [1/2 Bow] Dark Tan Part 11477 Element 6101254 Also in Tan ×16
  • Plate 1 x 1 Dark Tan Part 3024 Element 4549436 or 4497084 1 spare in the box Also in Tan ×26
  • Plate 1 x 2 Dark Tan Part 3023 Element 4528604 or 4497082 Also in Tan ×10
  • Plate 1 x 4 Dark Tan Part 3710 Element 4626904 or 4497088 Also in Tan ×18
  • Tile 1 x 1 with Groove Dark Tan Part 3070b Element 6055172 1 spare in the box Also in Tan ×12
  • Tile 1 x 2 with Groove Dark Tan Part 3069b Element 4496699 Also in Tan ×27

Light Bluish Gray 68 pieces

  • Bracket 1 x 2 - 1 x 4 [Rounded Corners] Light Bluish Gray Part 10201 Element 6014615 ×12
  • Brick 1 x 1 Light Bluish Gray Part 3005 Element 4211389 ×5
  • Brick 1 x 2 Light Bluish Gray Part 3004 Element 4211388 ×1
  • Brick Sloped 65° 2 x 1 x 2 Light Bluish Gray Part 60481 Element 4515374 ×4
  • Brick Special 1 x 1 with Headlight Light Bluish Gray Part 4070 Element 4211476 ×2
  • Brick Special 1 x 1 with Stud on 1 Side Light Bluish Gray Part 87087 Element 4558953 ×7
  • Hinge Brick 1 x 4 [Lower] Light Bluish Gray Part 3831 Element 4211461 ×1
  • Hinge Brick 1 x 4 [Upper] Light Bluish Gray Part 3830 Element 6327412 or 6011459 ×1
  • Hinge Plate 1 x 4 Swivel Top / Base - Solid Clip [Complete Assembly] Light Bluish Gray Part 73983 Element 6102769 or 4219256 ×2
  • Plate 1 x 1 Light Bluish Gray Part 3024 Element 4211399 1 spare in the box ×2
  • Plate 1 x 3 Light Bluish Gray Part 3623 Element 4211429 or 3623194 ×4
  • Plate 1 x 4 Light Bluish Gray Part 3710 Element 4211445 ×9
  • Plate 1 x 8 Light Bluish Gray Part 3460 Element 4211425 ×3
  • Plate 4 x 8 Light Bluish Gray Part 3035 Element 4211407 ×10
  • Plate 6 x 8 Light Bluish Gray Part 3036 Element 4211408 ×2
  • Plate Special 2 x 2 with Groove and Center Stud (Jumper) Light Bluish Gray Part 87580 Element 6126082 or 4565393 ×2
  • Tile 1 x 1 with Groove Light Bluish Gray Part 3070b Element 4211415 1 spare in the box ×1

Trans-Brown 54 pieces

  • Plate 1 x 2 Trans-Brown Part 3023 Element 6514006 or 6240219 ×9
  • Tile 1 x 1 with Groove Trans-Brown Part 3070b Element 6514259 or 6254253 1 spare in the box ×18
  • Tile 1 x 2 with Groove Trans-Brown Part 3069b Element 6514222 or 6251292 ×27

Dark Bluish Gray 14 pieces

  • Tile 1 x 3 Dark Bluish Gray Part 63864 Element 4568734 ×2
  • Tile 2 x 2 with Groove Dark Bluish Gray Part 3068b Element 4211055 ×4
  • Tile 2 x 4 with Groove Dark Bluish Gray Part 87079 Element 4560184 ×8

Black 10 pieces

  • Plate 2 x 10 Black Part 3832 Element 383226 ×4
  • Tile 1 x 6 with Groove Black Part 6636 Element 663626 ×2
  • Tile 1 x 8 with 'Flatiron Building' Print Black Part 4162pr0037 Element 6101020 ×1
  • Tile 1 x 8 with Groove Black Part 4162 Element 416226 ×3

Orange 1 piece

  • Brick and Axle Separator v2.0 Orange Part 96874 Element 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.

Request a replacement from LEGO

Buy the piece

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.

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