If a LEGO build seems to be missing a piece, start with the set number and the exact instruction step. That makes it easier to distinguish an overlooked part from a different color, a piece used too early, or a genuine missing component—and to describe the problem accurately if you need help.
Find the correct set before looking for a part
Use the set name or number printed on the box or building instructions. LEGO’s official Missing Pieces page begins with that search. If you are working on more than one set, keep each set’s information separate; the service requires separate requests for separate sets.
A franchise or character name is often too broad to identify the right inventory. Record the set number exactly, then compare the pictured model and the instruction booklet with the build in front of you. If a secondhand lot mixes pieces from several boxes, do not assume the number on the largest box describes every loose brick.
Recover the instructions first
If the booklet is lost, open LEGO’s building-instructions search. The official page lets you start with the set name or number and points to the LEGO Builder app for digital instructions. Match the set before downloading or following a guide; an alternate model or similar-looking edition can use different parts.
Keep the relevant step open while you inspect the remaining pieces. Look at the part from more than one angle, and compare the connection points and length as well as its color. For a modified build, return to the official instructions before concluding that an extra part should have been included.
Use a short search before submitting a request
- Separate the current build from loose pieces. Spread remaining parts on a tray or a clear surface where small elements are visible.
- Check opened packaging and the work area. Look inside bag folds and around the edges of the table. Keep small parts out of reach of younger children.
- Revisit the relevant steps. Check whether a similar piece was installed earlier where a different part belonged. Avoid taking apart the entire model until you have narrowed down the location.
- Compare the inventory when available. Note the part identifier, color and number needed rather than relying on a description such as “small gray connector.”
- Record the exact shortage. Distinguish one absent element from a whole missing bag or a damaged part. Those details help support understand the issue.
Keep a useful support note
| Field | What to record |
|---|---|
| Set | Full set name and set number from the matching box or instructions. |
| Build location | Instruction booklet, page and step where the part is needed. |
| Part | Identifier if available, color, shape and quantity missing. |
| Problem | Absent part, damaged part, missing bag, or uncertainty about the contents of a used set. |
| Purchase information | Retailer and receipt or order details if support asks for them; keep private information out of public comments. |
Follow the official form’s questions and choose the actual set and needed components. Do not submit repeated requests for the same issue while waiting for a response. For a problem the form does not describe clearly, use LEGO customer service and explain the difference rather than selecting an inaccurate reason.
Before buying a replacement
A missing part from a newly opened set, a piece lost from an older collection and an incomplete used purchase are different situations. Describe yours honestly. Do not assume a support request will be approved, that every discontinued part can be supplied, or that a delivery date is guaranteed. Use the response and terms for your actual request.
If you decide to purchase a replacement, compare the exact part identifier, color and quantity. Check the seller’s total including shipping; a bag of similar-looking pieces is not automatically a match. For a used set you have not bought yet, compare its inventory and missing components before deciding whether the complete project fits your budget.
Our shopping guides cover other checks to make before buying. You can keep the set number and required parts in the shopping list tools.
Official instruction-search and Missing Pieces destinations reviewed October 22, 2026. Support decisions and available replacement options depend on the actual request.