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.
781 pieces in 239 part and color combinations, plus 6 minifigures.
LEGO counts 801 pieces. This inventory comes from a separate parts catalog and lists 806, including the 25 parts inside the minifigures; 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.
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.
Equipment Wand [Individual]Reddish Brown ×2Dark Brown ×1Reddish Brown is redder and lighter than Dark Brown.
Bracket 1 x 2 - 1 x 2Black ×2Dark Bluish Gray ×10Black is darker than Dark Bluish Gray.
Brick 1 x 4Black ×3Dark Bluish Gray ×1Black is darker than Dark Bluish Gray.
Plate 1 x 2Black ×2Dark Bluish Gray ×8Black is darker than Dark Bluish Gray.
Plate 1 x 6Black ×2Dark Bluish Gray ×6Black is darker than Dark Bluish Gray.
Plate 2 x 4Black ×6Dark Bluish Gray ×4Black is darker than Dark Bluish Gray.
3 more look-alike pairs
Plate 4 x 6Black ×3Dark Bluish Gray ×2Black is darker than Dark Bluish Gray.
Plate 6 x 8Black ×1Dark Bluish Gray ×1Black is darker than Dark Bluish Gray.
Tile 2 x 2 with GrooveBlack ×4Dark Bluish Gray ×1Black is darker than Dark Bluish Gray.
Brick and Axle Separator v2.0OrangePart 96874Element 6240515 or 4654448×1
[No Color/Any Color]
1 piece
Sticker Sheet for Set 75955-1[No Color/Any Color]Part 39766Element 6237722×1
Minifigures
6 figures
Hermione Granger, Light Bluish Gray Hoodie with Stripes, Short LegsMinifigure, checked as a whole figure×1
Dementor, BlackMinifigure, checked as a whole figure×1
Harry Potter, Dark Blue Jacket with Zipper, Short LegsMinifigure, checked as a whole figure×1
Remus Lupin, Dark Bluish Gray Jacket over Olive Green VestMinifigure, checked as a whole figure×1
Trolley Witch, Dark Bluish Gray LegsMinifigure, checked as a whole figure×1
Ron Weasley, Light Bluish Gray Plaid Jacket with Zipper, Short LegsMinifigure, checked as a whole figure×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.