You have designed the MOC. You have spent hours in Stud.io or LDraw getting every angle right, every color dialed in, every structural connection tested. Now comes the part that stops most builders cold: sourcing the pieces. A complex MOC can require hundreds of unique elements across dozens of colors from parts that LEGO has not included in a retail set for years. Scrolling through BrickLink store by store, searching for each part individually, is a recipe for burnout, missed elements, and overspending on shipping.
BrickLink's wanted list system solves this problem completely. A wanted list is exactly what it sounds like — a persistent, editable list of every part, color, and quantity you need for a build. But it is far more than a shopping list taped to the fridge. It is a live database connected to every store on BrickLink. It can automatically find sellers who carry the most items from your list. It can alert you when parts drop to a target price. It can import directly from your digital building software. And it can consolidate what would have been twenty separate orders into three or four, saving you a small fortune in shipping. If you have read the BrickLink beginner's guide, you already know how to navigate the marketplace. Now it is time to learn the feature that separates casual browsers from serious builders.
This guide walks through every aspect of the wanted list system, from creating your first list to the XML bulk upload tricks that experienced builders use to manage projects with thousands of parts. Whether you are sourcing bulk bricks for a large display or hunting down five specific parts in dark azure, the wanted list is your command center.
A wanted list on BrickLink is a saved collection of items you intend to purchase. Each entry specifies a part number, a color, a condition (new or used), a desired quantity, and optionally a maximum price you are willing to pay. You can have multiple wanted lists simultaneously — one for your castle MOC, another for a spaceship project, a third for parts you always want to keep in stock. They persist in your account indefinitely, updating in real time as store inventories change across the platform.
The real power of a wanted list is not the list itself but what BrickLink does with it. Once your list exists, BrickLink's matching engine can scan every store on the platform and tell you exactly which sellers carry which parts from your list, how many of your items each store can fulfill, and what the total cost would be. This transforms parts sourcing from a manual, part-by-part treasure hunt into an automated, optimized process. You go from asking "who has this piece?" to asking "which three stores can fill my entire list for the lowest combined cost including shipping?"
Wanted lists also serve as project management tools. As you order parts and they arrive, you can update quantities or remove fulfilled items. You can share wanted lists with other builders working on collaborative projects. You can duplicate a list, modify it, and use the copy for a variant of the same build. Think of each wanted list not as a shopping cart but as a living blueprint of everything standing between your digital design and a physical model sitting on your shelf. For builders coming from other marketplaces, the BrickLink vs. Pick a Brick vs. Amazon comparison explains why wanted lists give BrickLink a decisive advantage for MOC sourcing.
Start by logging into your BrickLink account and navigating to the "Want" section in the top menu. Click "Add to Wanted List" or go directly to your wanted list management page. BrickLink will prompt you to create a new list if you do not already have one. Give it a descriptive name — "Medieval Castle Tower" is more useful than "List 1" when you have six projects running simultaneously. You can also assign a list ID, though BrickLink will auto-generate one if you leave it blank.
Adding individual items is straightforward. Search for a part by its BrickLink ID, LEGO element number, or description. When you find the part, click "Add to Wanted List" and specify the color, quantity, condition preference, and any price remarks. For example, you might add part #3005 (1x1 Brick) in Dark Bluish Gray, quantity 48, condition New, with a remark noting it is for the tower base. Repeat for every part in your build. For small projects with twenty or thirty unique elements, this manual approach works fine. For anything larger, you will want to use the import and XML features covered in the next sections.
A few tips for list setup: always specify color. A wanted list entry for "1x1 Brick" without a color is nearly useless because the auto-match system will not know which inventory to check. Always set your condition preference. Mixing new and used parts in a single order is fine, but knowing which parts absolutely must be new (visible exterior pieces) versus which can be used (hidden structural elements) will save you money. And consider your quantity padding — experienced builders often add five to ten percent extra on small, easily lost parts like 1x1 plates and Technic pins. You would rather have a handful of spares in the parts bin than discover you are three pins short at midnight on build day.
If you design your MOCs digitally — and you should — then importing a parts list directly into BrickLink is the fastest way to populate a wanted list. Stud.io, which is owned by BrickLink, has the tightest integration. Open your model in Stud.io, go to File, then Export, and select "Upload to BrickLink Wanted List." Stud.io will generate a complete bill of materials, map every element to its BrickLink catalog entry, and push the list directly to your account. The entire process takes less than a minute for even complex models.
LDraw-based tools like BrickLink Studio, LeoCAD, or MLCad require an extra step. Export your model's parts list as an LDR or XML file. Then log into BrickLink, navigate to your wanted list, and use the "Upload" function to import the file. BrickLink will parse the file, match parts to its catalog, and add them to your list. Occasionally, a part mapping will fail — LDraw and BrickLink use slightly different numbering systems for some elements. When this happens, BrickLink will flag the unmatched parts so you can add them manually. Keep an eye on alternate part numbers. BrickLink often lists mold variants and redesigned versions of the same basic element under separate IDs, and your LDraw file might reference one variant while the sellers stock another. The Parts Lab is a good resource for understanding which element variants are functionally interchangeable.
A lesser-known feature: Stud.io can also export a "Want" file that includes not just part numbers and colors but also substitute elements. If your design uses a part that is rare or expensive, Stud.io can suggest alternatives that achieve the same connection geometry. This is invaluable for parts that have been out of production for years or exist in limited color runs. Import the substitutes into your wanted list as secondary options, and you will have fallback sources if the primary part is unavailable. Digital design to wanted list is not just a convenience — it is the workflow that makes ambitious MOCs financially viable.
Auto-match is the single most important feature in the wanted list system, and it is the one that most new BrickLink users either overlook or underestimate. Here is what it does: you click "Buy All" on your wanted list, and BrickLink scans its entire marketplace to find the combination of stores that can fill your list with the fewest orders, the lowest total cost, or the best balance of both. It ranks stores by how many of your wanted items they carry, their prices, their location (for shipping cost estimation), and their seller feedback ratings.
The results page shows each matching store with a percentage indicating how much of your list that store can fulfill. A store showing 78% means it carries 78% of the unique items on your list in the quantities you need. The trick is to start with the highest-percentage stores and work down. Your first order from a store covering 60-70% of your list will knock out the bulk of your needs. Your second order from a store covering 40-50% of the remaining items closes most of the gap. Usually, three to five stores can fill a list of several hundred unique elements. Without auto-match, you would spend hours cross-referencing inventories manually. With it, the process takes minutes.
Tune your auto-match results using the filter options. You can restrict results to stores in your country (saving on international shipping), require a minimum feedback score, limit results to new-only or used-only parts, and set a maximum price per lot. For builders in the United States, filtering to domestic stores often cuts shipping costs by half or more compared to ordering from Europe. For rare parts that only a few stores worldwide carry, remove the location filter and accept the international shipping cost as the price of building something unique. The BrickLink beginner's guide covers seller evaluation in more detail, but for auto-match purposes, any store with 99% or higher positive feedback and at least 100 orders is a safe bet.
Shipping costs are the silent killer of BrickLink budgets. The parts themselves are often surprisingly affordable — common elements cost fractions of a cent each. But each order carries a separate shipping charge, and if you are placing ten orders to fill one wanted list, those shipping costs can exceed the cost of the parts themselves. Order consolidation is the discipline of minimizing the number of separate orders required to fill a list, and it is where wanted lists pay for themselves many times over.
The strategy is simple in principle: buy as many parts as possible from as few stores as possible. Auto-match handles the heavy lifting, but you can optimize further by adjusting your list before running the match. Consider relaxing color requirements on hidden parts. If your build uses 200 dark bluish gray 1x2 plates buried inside a wall where they will never be seen, changing those to "any gray" doubles or triples the number of stores that can fill that line item. Similarly, accepting used condition on structural parts dramatically increases availability. A used 2x4 brick is functionally identical to a new one for interior framing.
Another consolidation technique is combining projects. If you have three wanted lists for three different builds, merge them into a single list before running auto-match. A store that carries 40% of each individual list might carry 65% of the combined list, turning three separate orders into one. You will sort the parts back into project groups when they arrive — a few labeled bags and a printout of each project's parts list makes this manageable. For large-scale builders working on display layouts, combining multiple module lists into a single sourcing run can reduce total shipping costs by 40-60%. The bulk bricks sourcing guide goes deeper on volume purchasing strategies that complement this approach.
Not every build needs to be sourced immediately. Sometimes you are designing months ahead of a convention display, or you are working on a passion project with no deadline. In these cases, BrickLink's notification system lets you set price targets and wait for the market to come to you. This is particularly valuable for expensive or rare elements where prices fluctuate significantly based on supply and demand.
To set a price alert, edit an item in your wanted list and enter a value in the "Max Price" field. BrickLink will notify you when any store lists that part at or below your target. You can set alerts on individual items or apply a blanket maximum across your entire list. The notification arrives via email, and the listing that triggered it includes a direct link to the store. For parts with volatile pricing — retired minifigure accessories, rare printed tiles, discontinued colors — price alerts can save you substantial money. A part that averages two dollars might dip to fifty cents when a seller liquidates a large collection. If your alert is set, you catch that dip. If it is not, the parts are gone before you notice.
A smarter approach is to use the BrickLink price guide for each item on your list before setting your maximums. The price guide shows the average sale price, the minimum, and the maximum over the past six months. Set your alert at or slightly above the six-month average for fair-value sourcing, or at the six-month minimum if you are willing to wait for a deal. For common parts, the average is almost always available immediately. For rare parts, patience and a well-set alert system will eventually fill every line on your list. This is the long game of AFOL building, and wanted lists make it systematic rather than chaotic.
For power users, manual entry and even Stud.io imports are too slow. BrickLink's XML upload feature lets you create or modify a wanted list by pasting or uploading raw XML code. This is the fastest way to add hundreds of items at once, duplicate and modify lists programmatically, or integrate BrickLink with external tools and spreadsheets. If that sounds intimidating, it should not — the XML format is simple and repetitive.
The basic structure looks like this:
<INVENTORY>
<ITEM>
<ITEMTYPE>P</ITEMTYPE>
<ITEMID>3005</ITEMID>
<COLOR>85</COLOR>
<MINQTY>48</MINQTY>
<CONDITION>N</CONDITION>
<NOTIFY>N</NOTIFY>
</ITEM>
</INVENTORY>Each <ITEM> block represents one line on your wanted list. ITEMTYPE is P for parts, S for sets, M for minifigures, or B for books. ITEMID is the BrickLink catalog number. COLOR is the BrickLink color ID (85 is Dark Bluish Gray, 11 is Black, 1 is White — the full list is on the BrickLink color guide page). MINQTY is how many you need. CONDITION is N for new or U for used. Wrap as many <ITEM> blocks as you need inside the <INVENTORY> tags, paste the XML into the upload field on the wanted list page, and click submit. Your entire list populates in seconds.
Where this becomes truly powerful is in spreadsheet-to-XML workflows. Build your parts list in a spreadsheet with columns for part number, color ID, quantity, and condition. Use a simple formula or script to convert each row into the XML block format above, then concatenate the results with the inventory wrapper tags. Some builders maintain master spreadsheets with every part they have ever used across all projects, generating wanted lists on demand for any combination of builds. There are also community-built tools that automate this conversion — search the BrickLink forums for "XML generator" and you will find several options. For builders managing multiple large-scale projects simultaneously, XML upload is not optional. It is the only workflow that scales.
Maintain a "pantry list." Beyond project-specific wanted lists, keep a standing list of parts you always want to have on hand: common connectors, Technic pins, 1x1 plates in core colors, tile assortments. Whenever you place an order from a store for a project, check if that store also carries items from your pantry list. Adding a few common parts to an existing order costs almost nothing in marginal shipping but slowly builds a reserve that makes future projects faster to complete. The LEGO sorting guide covers how to organize these reserves so you can actually find them when you need them.
Use the "Easy Buy" wisely. BrickLink's Easy Buy feature automates the ordering process by selecting stores and placing orders on your behalf based on your auto-match results. It is convenient but aggressive — it will place orders immediately, and you cannot review individual store carts before committing. Use Easy Buy only for small lists of common parts where any store with good feedback will do. For large, complex lists or lists with rare parts, manually review the auto-match results and place orders yourself. The control is worth the extra five minutes.
Check store minimums. Many BrickLink stores have minimum order amounts, typically between one and five dollars. If auto-match sends you to a store for a single fifty-cent part, you will need to add filler items to meet the minimum. This is another reason pantry lists are valuable — filler items that you actually need are better than random parts bought just to hit a threshold. Before committing to an order, check the store's terms page for minimums, handling fees, and shipping policies. A store with slightly higher part prices but free shipping over ten dollars often beats a store with rock-bottom prices and a five-dollar flat shipping fee.
Leverage existing sets as part packs. Sometimes the cheapest way to source a large quantity of a specific part is to buy a set that contains it. A retired City set might include 30 dark bluish gray 1x2 plates that would cost more to source individually than the entire set costs on the secondary market. BrickLink's "Set Inventories" tool lets you see every part contained in any set. Cross-reference your wanted list against set inventories to identify these opportunities. This is particularly effective for parts in unusual colors that were only produced in one or two sets.
Document your process. After you have sourced a few builds, you will develop preferences — favorite stores, optimal order sizes, acceptable substitutions for specific parts. Write these down. A simple text file listing your go-to stores by region, your standard color substitution rules, and your pantry list items will save time on every future project. The builders who source large MOCs efficiently are not smarter than everyone else. They have systems.
Ignoring color IDs. BrickLink distinguishes between colors that look nearly identical in person. Light Bluish Gray (LBG, color 86) and Light Gray (color 9) are different items in the catalog even though they are hard to tell apart in photographs. If your Stud.io model uses LBG but your wanted list imports as Light Gray, you will receive the wrong parts. Always verify color IDs during import, especially for grays, blues, and greens where legacy and modern colors coexist in the catalog. The AFOL glossary covers common color terminology that will help you navigate these distinctions.
Ordering without checking your own inventory. Before sourcing a wanted list, go through your existing parts collection. You may already have twenty of the forty dark red 1x4 plates your build requires. Updating the wanted list to reflect what you already own prevents duplicate purchases and reduces the number of items each store needs to fulfill, making auto-match more effective. The sorting guide makes this inventory check practical rather than theoretical — you can only check what you have if you know where it is.
Neglecting condition notes. "Used" on BrickLink covers a wide range. A part listed as used might be virtually indistinguishable from new, or it might have bite marks, discoloration, or scratches. If condition matters for your build — and it always matters for visible exterior surfaces — specify "new" for those items even if it costs slightly more. Reserve "used" for structural internals, Technic framing, and any part that will be completely hidden in the finished model. This is not snobbery. It is material management. You are building something you will look at for years. Visible surfaces deserve clean parts.
Panic-ordering rare parts. When you see a rare part on your wanted list with only two or three sellers worldwide, the instinct is to buy immediately before it disappears. Resist. Check the price guide first. If the current listings are at the six-month high, waiting a few weeks often produces a better option. Rare parts appear and disappear from BrickLink as sellers list new inventory and collections enter the market. Set your price alert and be patient. The exception is truly unique elements — parts from a single limited set that rarely appear for sale. For those, act quickly and pay fairly. You may not get another chance.
The journey from a wanted list to a completed MOC is one of the most satisfying arcs in the LEGO hobby. It starts with a design that exists only as pixels on a screen and ends with a physical model you can hold, rotate, and display. The wanted list is the bridge between those two states, and mastering it means removing the logistical friction that stops ambitious builds from ever leaving the planning stage.
Here is a workflow that works. Design your model digitally. Export to a wanted list. Audit the list against your existing inventory and remove parts you already own. Run auto-match and identify your top three to five stores. Review each store's cart, check minimums and shipping, add pantry items as needed. Place your orders. Track shipments. When parts arrive, sort them by sub-assembly using your digital model's exploded view or step groups. Build. Inevitably, you will discover that one part does not fit quite right, or a color looks different in person than it did on screen. Make a note, adjust your digital model, and update the wanted list for next time. Every build teaches you something about the sourcing process that makes the next build smoother.
The wanted list system is not glamorous. It does not produce the dopamine hit of snapping a perfectly engineered connection together or the satisfaction of stepping back from a finished display. But it is the infrastructure that makes all of that possible. Without it, MOC building at any serious scale is an exercise in frustration — hunting for parts, overpaying for shipping, discovering gaps in your inventory at the worst possible moment. With it, you have a system. And systems are what turn ideas into bricks.
A great MOC starts with a wanted list. Build the list right, and the model builds itself.
Ready to start sourcing? Head to BrickLink and create your first wanted list. For build inspiration, browse the Builds hub and the 10 MOC ideas from existing sets. For gear and new releases, the LEGO Shop has you covered. Now go fill that list.