Depth should match how confident you are and how easily you can reorder, not how much you like the product. A style you have never sold, from a supplier who can ship again in a week, deserves the smallest order the supplier allows. A style you have already sold out of twice, from a supplier with long lead times and limited stock, deserves real depth. Everything else sits between those two, and the deciding factors are size run, case pack, reorderability, and how much of your budget one style can safely hold.
I am Carina Hatton, a boutique owner since 2013 and an ecommerce coach since 2019. This is the depth companion to the guide on how many styles to start with. Read them together, because breadth and depth come out of the same budget.
Quick answer
What actually sets depth
| Factor | Pushes depth down | Pushes depth up |
|---|---|---|
| Evidence | Never sold this style, brand, or category | Sold out of it before, or a close sibling of it |
| Reorderability | Supplier restocks quickly and reliably | Limited run, long lead time, or one-time production |
| Season length | Short window left to sell | Year-round or early in the season |
| Price point | High ticket, so each unit ties up more cash | Low ticket impulse item |
| Size run | Wide range of sizes to cover | One size fits most |
| Case pack | Supplier allows piece buying | Fixed pack you cannot break |
| Cash position | Tight budget with no reorder reserve | Healthy reserve and a proven seller |
Apparel: depth is a size question
You are not really choosing how many units of a top to buy. You are choosing how many of each size, and the unit count is what falls out. That is why flat rules like "buy six of everything" fall apart the moment a size run has five sizes in it.
A few things hold true regardless of who you buy from. Your size demand is specific to your own customer, so the only reliable curve is the one your own sales produce. Until you have that data, the vendor's pack is a starting assumption rather than a fact. Track sales at the size level from the first week, not just by style, because a style that looks like a winner is often one or two sizes carrying the whole result.
Two practical habits help before you have history. First, never buy a size run so deep that a single slow size becomes a markdown pile. Second, write down the sizes you ran out of first, because that list is the most valuable thing your opening buy produces. There is more on managing this in boutique inventory management.
Accessories and gifts: depth is a demand bet
One-size items remove the size problem and replace it with a pure demand question. If you buy twelve of a necklace, you are betting that twelve people want that exact necklace inside your selling window. That can be a great bet on a low-cost impulse item at the counter, and a poor one on a statement piece at a higher price.
Gifts and accessories also behave differently in a store than apparel does. They sell as add-ons, they sell hardest around gifting occasions, and they need visible quantity to look like a display rather than a leftover. A single candle on a shelf does not sell; a stack of them does. That is a merchandising argument for depth on low-cost items even when the pure demand math says otherwise.
Case packs and minimums often decide for you
Plenty of suppliers do not let you choose depth at all. A case pack is the smallest sellable increment, and if the case is a preset size run, the depth decision is made the moment you pick the style. Others set a per-style minimum, a per-color minimum, or a total order value you must reach, which quietly pushes you into more depth than you planned.
Before you build a buy sheet, get the opening minimum, the reorder minimum, the case pack, whether the pack is a fixed size run, and whether substitutions are allowed. The MOQ guide walks through every minimum type and how to ask about them. Also confirm the reorder terms, because a supplier with an easy reorder makes shallow testing safe, and a supplier with a high reorder minimum makes it a trap.
When 2, 4, 6, or 12 units make sense
These are situations, not prescriptions. The right number is whatever the situation and the supplier's pack structure allow.
| Depth | Typical situation | Watch out for |
|---|---|---|
| 1 to 2 units | A true test, a high-ticket piece, a one-of-a-kind or local maker item, or a sample you want to photograph before committing | Sells out instantly and teaches you nothing except that one person wanted it |
| 3 to 4 units | A new accessory or gift item at a moderate price, or a piece-buy apparel style where you only want the core sizes | Too thin to hold a display and too shallow to survive a good week |
| 6 units | A common case pack, and a workable first buy on an apparel style with a short size run or a one-size accessory you believe in | Across a five-size run this is barely one per size |
| 12 or more | A proven repeat seller, a low-cost impulse item that needs presentation quantity, a full size run pack, or a gifting-season buy placed with lead time | A large share of your budget behind a single bet, and markdown exposure if the season closes |
The concentration rule that protects your launch
Whatever depth you choose, check the concentration. If one style holds a large slice of your opening inventory dollars, your launch result is that style's result. Spreading that same money across a few styles with sensible depth gives you several chances to find the winner, and the winner is what the reorder budget is for.
A quick way to test it: list each style with its landed cost times units, then look at the percentage column. If any untested style is sitting high in that list, either cut its depth or move it to the proven column with evidence you can name. The First Wholesale Order Allocator does this split for you, and how to split your first wholesale order explains the reasoning behind it.
A worked hypothetical opening buy
Numbers below are illustrative, not quotes or recommended amounts.
Say a new boutique has $3,000 for product after holding a reorder reserve back. The owner builds it like this: two core apparel styles at a six-piece pack each, one higher-priced dress bought shallow at two units, three one-size accessory styles at four units each, and one low-cost gift item at twelve because it needs to look like a display and it is inexpensive per unit. The apparel carries the store's identity, the dress is a test, the accessories add basket size, and the gift item fills the counter.
Now check the cash. If the dress lands at $38 per unit, two units is $76, which is a small, sensible test. If the same owner had bought six, that single unproven style would be holding more than double the dollars of the accessory group combined. That is the trade the concentration check is designed to catch.
Run the same exercise with your own supplier pricing, including inbound freight, using the Landed Cost Calculator and the landed cost guide.
Turning the first buy into a reorder plan
Depth on the second order should come from data, not instinct. Look at how fast each style sold, which sizes went first, whether the supplier still has stock, how much season remains, and whether the style was profitable after freight and returns. A style that sold out in ten days with even size movement is a different reorder from one that sold out because a single size was underbought.
Use the Sell-Through Calculator to rank styles against each other, and the Reorder Point Calculator to set the unit level that triggers the next order given your lead time. The theory behind both is in retail math formulas.
Check the price before you commit the depth
Depth and price are linked. If a style only leaves a thin margin after landed cost, buying twelve of it multiplies a weak decision. Price the style first, confirm the margin holds after freight, fees, and expected markdowns, and only then decide depth. Work through retail pricing and how to price boutique clothing, and check the numbers in the Profit Margin Calculator.
Size distribution without a rigid formula
There is no single size curve that is correct for every boutique, and anyone who hands you one is guessing about your customers. What is true is that demand is never evenly spread, so buying one of every size is almost always the wrong answer once you have any information at all.
Until you have your own data, the safest approach is to weight the middle of whatever run your vendor offers, keep the ends shallow, and treat the first order as a measuring exercise. Once you have sold through a few styles, your own numbers take over and the question stops being difficult.
| Situation | How to handle sizes |
|---|---|
| No sales history at all | Weight the middle sizes, go shallow at both ends, and accept that the first buy is partly research |
| Vendor sells a fixed size run | Take the run as offered and record which sizes stranded, so you know what to ask for next time |
| A few months of your own data | Build the run from your actual size-level sell-through rather than a generic curve |
| You serve a defined size range | Buy the range you actually serve properly instead of thinly covering sizes you rarely sell |
| Fit is inconsistent between vendors | Treat each vendor's sizing separately and publish measurements rather than size names alone |
Track sales at size level from the first week. Style-level reporting hides the most useful signal in the store, which is a style that sold out of two sizes and never touched the rest. That style did not perform well, it performed well in part of the run, and the reorder should reflect that.
Stranded sizes are a cost, not just an annoyance. A style that sells 80% of its units and leaves the rest to be marked down has a different real margin than the shelf price suggests, which is why depth decisions and pricing decisions belong in the same conversation. Work the effect through with the Markdown Calculator.
What depth looks like after the first reorder
Opening depth and ongoing depth are different problems. On the opening order you are protecting yourself against being wrong, so you go shallow and spread the risk. Once a style has sold, you are backing something you have evidence for, and being too cautious costs you sales you had already earned.
After the first cycle, depth should follow performance rather than fairness. Proven repeat sellers earn deeper buys and a standing reorder trigger. Styles that sold acceptably but not enthusiastically get the same shallow treatment again. Styles that did not move do not come back, whatever you paid for them.
Lead time is the other input that changes. If a supplier ships in a few days, you can run lean and restock quickly, and shallow depth costs you almost nothing. If the supplier takes weeks, or the product is seasonal and the season is short, shallow depth means being out of stock during the window that mattered. Set the actual trigger quantity in the Reorder Point Calculator, using your sales rate and that supplier's real lead time rather than an assumption.
One more thing changes after the first order: your relationship with the vendor. Vendors who have shipped to you before are often easier to talk to about pack flexibility and substitutions, which can quietly improve your depth options over time. It is worth asking, and worth being a customer who pays on time.
Common depth mistakes
- Buying the same unit count for every style regardless of size run or price.
- Going deep on a brand you have never sold because the wholesale price looked good.
- Ignoring the size run and discovering the pack was weighted toward sizes your customer does not buy.
- Buying so shallow that a good style sells out before it can teach you anything.
- Committing depth to a seasonal item too late in its window.
- Forgetting freight when comparing a deeper pack against a shallower one.
- Reordering on gut feel instead of size-level sell-through.
What to do next
- Confirm each supplier's pack, opening minimum, and reorder minimum.
- Calculate landed cost per unit, freight included.
- Set retail prices and confirm the margin survives markdowns.
- Assign depth by evidence, reorderability, and season length.
- Check concentration so no untested style dominates the buy.
- Track sell-through at the size level and let it write the reorder.