Open-to-buy mistakes are planning errors that bring in more inventory than sales can absorb, so cash leaves before it comes back. This guide covers ten, each with illustrative math showing the cash at stake and the fix. Every one traces back to a single formula: planned sales plus planned markdowns plus planned end-of-month inventory, minus beginning-of-month inventory.
Why Open-to-Buy Mistakes Show Up in the Bank Account First
Open-to-buy (OTB) is the dollar amount of new inventory a store can receive in a period without overshooting its stock plan. Every dollar of OTB you spend becomes a vendor invoice weeks or months before it becomes a sale.
Cash Margin Partners uses the standard retail method, worked line by line in our definitive guide to open-to-buy planning. These are the four formulas every mistake below refers back to:
- Retail OTB = planned sales + planned markdowns + planned end-of-month (EOM) inventory, minus beginning-of-month (BOM) inventory.
- Cost OTB = retail OTB × (1 minus initial markup %).
- OTB still available = retail OTB minus stock already on order at retail.
- Planned BOM inventory = stock-to-sales ratio × planned sales.
Take the illustrative boutique from that guide. May planned sales are $54,000, planned markdowns $5,400, planned EOM inventory $180,000 and BOM inventory $178,200. Retail OTB comes to $61,200, or $27,540 at cost with a 55% initial markup.
Rent, payroll and next season's buy all draw on the same account. That makes retail cash flow and open-to-buy one conversation. When the plan is wrong, the error lands in the back room, where cash goes to sit down and stop moving.
Cash Margin Partners is an inventory cash-recovery practice for independent, owner-operated retailers. We show owners how much cash sits trapped in unsold inventory, then give them a prioritized plan to get it back.
1. Reordering Last Season's Buy Instead of Last Season's Sales
The first mistake is copying last season's purchase orders. A repeated order repeats the leftovers too, because it's sized to what you bought with no correction for what sold.
Sell-through is the share of units received that sold during the period. It's the number that should size a reorder, and a repeat buy ignores it.
Illustration: last spring the boutique bought 400 units of a linen dress at $38 cost, $15,200 in all. It sold 260 of them, a 65% sell-through. Reorder the same 400 and you've committed 140 units, or $5,320 at cost, to the back room before the season opens.
How to Size the Reorder From Sell-Through
Start with the units you expect to sell, then divide by the sell-through rate you're aiming for. At an 80% target, 260 expected sales means buying 325 units, or $12,350 at cost. That's $2,850 less cash out the door than the repeat order.
Check for stockouts before you trust the history. If the dress sold out in week five, 260 understates demand, so note it before the number becomes a plan.
For a rough sense of what past buys have already left behind, try the free trapped-cash estimate. It asks a few questions about your store and returns a directional dollar range.
2. Counting Dead Stock and Shrink as Beginning-of-Month Inventory
BOM inventory in the OTB formula should be stock that can sell. Pulled straight from the point-of-sale system, the figure can include dead stock and units that walked out the door. The plan looks covered while the selling floor runs thin.
Dead stock is inventory with no verified sales over the measured window. It sits in the BOM figure, counts toward the stock plan and supports no sales at all.
Shrink widens the gap between the system and the shelf. The National Retail Federation's 2023 National Retail Security Survey put average shrink at 1.6% of sales in fiscal 2022, up from 1.4% the year before.
That survey drew on 177 retail brands with more than 97,000 locations. Use it as a reference point for your own count.
Illustration: the boutique's book BOM is $178,200 at retail. An aging report shows $19,800 of it in styles with no sales in 180 days. The plan treats all $178,200 as sellable, the sellers run short, and $8,910 at cost stays parked in the back room.
How to Plan on Sellable Stock and Give Aged Stock Its Own Exit
Run an inventory aging report and split BOM into sellable and aged stock before you calculate OTB. Plan receipts against the sellable figure only.
The aged goods get a separate exit plan with dates attached for markdowns, bundles or liquidation. These markdown tactics for dead stock cover the options, and whatever cash comes back can fund part of the gap in sellers.
Count the high-shrink categories before the plan closes. A cycle count on your top styles takes an afternoon and corrects the number the whole plan rests on.
3. Forgetting What's Already on Order
OTB still available equals retail OTB minus everything already on order at retail. Skip that subtraction and you'll write new orders against money that's already promised to vendors.
Illustration from CMP's open-to-buy guide: after a slow spring, the boutique's revised May OTB fell to $28,000 at retail. Another $44,000 was already on order, so the true position was negative $16,000. Reading $28,000 as available and spending it puts the store $44,000 at retail over plan, about $19,800 at cost.
How to Keep an On-Order Log by Delivery Month
List every open purchase order by delivery month, at retail and at cost, with its cancel date. Subtract the total from OTB before you meet a single vendor.
Cancel dates matter most when the number goes negative. An order you can still cancel is the cheapest cash fix on this list, because the money never left the account.
Key insight
Negative open-to-buy is a cash signal. It means vendors already hold orders for more inventory than the plan can absorb. The fix starts with purchase orders you can still cancel or push back.
4. Setting End-of-Month Stock by Feel
Planned EOM inventory should come from a stock-to-sales ratio. That ratio compares stock on hand at the start of a month with that month's sales. Set it by how full the floor looks, and the plan grows a little every season.
Planned BOM inventory equals the stock-to-sales ratio times planned sales. One month's planned BOM is the prior month's planned EOM, so an inflated ratio inflates every receipt in the season.
Key data point
The Census Bureau's inventories-to-sales ratio for clothing and clothing accessory stores was 2.11 in July 2026, seasonally adjusted (FRED series MRTSIR448USS). For all retailers it was 1.27 in the same month (FRED series RETAILIRSA).
Both are national aggregates measured on a different basis from a store's stock-to-sales ratio. Read them as context and set your own target from your own history.
Illustration: a hypothetical gift shop plans $40,000 in November sales. At a stock-to-sales ratio of 2.5, it needs $100,000 at retail on November 1. The owner wants a fuller floor and plans 3.0, or $120,000.
That extra $20,000 at retail is $9,000 at cost at the same 55% markup. All of it gets bought before a single holiday customer walks in.
How to Set the Ratio From Your Own Sell-Through History
Pull last year's BOM inventory and sales by month and calculate the ratio you ran. Then check sell-through in the months you ran heavy; if the extra stock didn't lift sales, it only lifted carryover.
CMP's open-to-buy guide uses working ranges of 2.5 to 4.0 for apparel and 2.0 to 3.0 for gift. Start at the low end and add stock only where sell-through earns it.
5. Keeping the Original Plan After Sales Miss
An open-to-buy plan is a forecast, and it needs a fresh forecast every month against what sold. When sales run under plan and receipts don't change, the difference lands in EOM inventory.
Illustration: CMP's guide plans $126,000 in spring sales through April, and the boutique sold $115,100, 8.7% under. That's $10,900 at retail of goods bought for sales that never happened. At a 55% markup, about $4,905 at cost carries into May unless receipts are cut.
How to Reforecast Monthly and Cut the Next Receipt
Close each month by comparing sales, markdowns and receipts with plan. Carry the miss forward: lower the next month's planned sales, then recalculate OTB and check open orders against it.
Compare months on a 4-5-4 retail calendar so an extra weekend doesn't read as a trend. The National Retail Federation's 4-5-4 calendar gives comparable months the same number of Saturdays and Sundays, so like days get compared.
Operator tip
Agree on reforecast triggers before the season starts. For example, any category running more than 10% under plan for two straight weeks gets its next delivery reviewed that same week.
Your own version of that $4,905 is sitting in your sales history right now, spread across specific SKUs. A free workspace connects read-only to Shopify, Square or Lightspeed Retail X-Series, or takes a spreadsheet upload. It shows the trapped cash item by item. Direct availability depends on production launch status and workspace eligibility; compatible item-level exports remain available after column review.
Lightspeed runs through a capacity-managed app that may pause new connections, so availability depends on workspace eligibility (details on the integrations page).
6. Committing the Whole Season at the Trade Show
OTB is a ceiling on receipts, and spending all of it in one week leaves nothing for what the season teaches you. Winners sell out with no budget left to reorder them, and the reorder gets written on top of a full plan anyway.
Illustration: a store with $60,000 in spring cost OTB commits all of it at a January show. By week six, two lines have sold through and three are lagging, with $9,000 at cost still on the floor. Reordering the winners for $6,000 puts the store $6,000 over plan while the $9,000 sits.
How to Hold a Reserve for In-Season Reorders
Commit part of the season's cost OTB up front and hold the rest for reorders on proven sellers. As an example, a 20% reserve on $60,000 keeps $12,000 open for whatever sells in the first six weeks.
Ask vendors at the show about in-season lead times and reorder minimums. A line you can't reorder mid-season deserves a smaller opening buy, because that opening buy is the only one you'll get.
7. Budgeting at Invoice Cost Instead of Landed Cost
Cost OTB is the cash budget, so it has to include every dollar it takes to get goods onto the floor. Freight, duties and tariff surcharges that sit outside the invoice push cash out past the plan.
Those costs have been climbing. In the Federal Reserve Banks' 2025 Small Business Credit Survey, 69% of retail firms reported tariff-related cost challenges, the highest share of any industry. The survey ran from September to November 2025 and drew 6,525 responses from small employer firms.
Illustration: the boutique's May cost OTB is $27,540, calculated on invoice cost. Freight and duties add 9% on top, so the same goods take $30,019 in cash, $2,479 over budget. If retail prices stay put, the initial markup also slips from 55% to about 51%.
How to Calculate Cost OTB on Landed Cost
The cost complement is one minus the initial markup percentage, and it converts retail OTB into cost OTB. Build a landed-cost factor per vendor from recent shipments: freight, duties and fees divided by invoice value. Apply it to the cost complement before you set the cash budget.
Then decide, line by line, whether to raise retail, cut units or drop the line. Any of those choices can work; leaving the plan at invoice cost is how the overrun stays hidden until the bills arrive.
8. Buying to Vendor Minimums and Price Breaks
A price break saves money only on units you'd have sold anyway. Every unit bought past demand to reach the break is cash parked in the back room, earning nothing until it sells.
Illustration: a store needs 72 units of a candle that sells 6 a week. The vendor charges $12.00 a unit, or $10.80 a unit at 144. The bigger order costs $1,555.20 against $864.00, so $691.20 more leaves the account.
The discount saves $86.40 on the 72 units you needed. In exchange, $777.60 of extra stock covers 12 more weeks of sales, assuming the rate holds.
How to Run the Break-Even Before You Take the Deal
Compare the discount on needed units with the cash the extra units will hold, and for how long. If the extra stock would take longer to sell than your normal reorder cycle, pass on the break.
Vendor minimums work the same way. If a minimum pushes a line over plan, ask for a split shipment or a smaller assortment first.
9. Planning the Whole Store as One Number
A store-level OTB hides category problems, because overages in one class cancel shortages in another. Plan OTB by category at minimum, and by location if you run more than one store.
Store example
Take a hypothetical shoe and accessories boutique that plans $40,000 of EOM inventory in each category. Accessories finish the month at $52,000 and footwear at $28,000.
The store total lands exactly on plan at $80,000. Meanwhile footwear sizes break, and $5,400 at cost sits in accessories nobody asked for.
How to Split the Plan by Category and Location
Run the formula separately for each category, with its own sales plan, markdown plan and stock-to-sales ratio. The store total is the sum of those lines and nothing more.
Owners with more than one store should add location to the plan. A transfer between stores can fix a category imbalance before anyone writes a new purchase order. If you're picking a spreadsheet to run this in, our roundup of open-to-buy templates compares the options.
10. Skipping the Season-End Review
The season-end review is where open-to-buy pays off, because it measures what the last buy did to cash. Skip it and next season's plan gets built on memory, which reliably remembers the winners.
Carryover is the share of a season's receipts, at cost, still on hand when the season ends. It's the clearest single measure of how much of last season's buy moved into the back room.
Illustration from CMP's open-to-buy guide: the boutique closed spring at 74% sell-through, with $27,350 at cost left over. That's a 25.6% carryover against a 15% target. On $106,875 of receipts at cost, the excess over target comes to about $11,300.
How to Review Every Line Before You Plan the Next Season
For each line, record units received, units sold, sell-through, markdown dollars and leftover cost. Then mark each one: reorder at the same depth, buy shallower, test once more or drop.
This is the step Cash Margin Partners was built for. CMP connects read-only to your store data and shows, SKU by SKU, where last season's buy is still holding cash. With enough supported sales history and cost data, CMP estimates 30, 60 and 90-day cash-at-risk, so the next plan starts from evidence. Forecasts and predictive alerts require a recent successful supported live connection and sufficient history and cost evidence; model projections are not guarantees.
How to Prioritize These Fixes for Your Store
Fix them in the order the cash leaves. Open orders come first, because a cancel date is a deadline and that money hasn't moved yet.
- This week: on-order and reserve (mistakes 3 and 6). Log every open purchase order, subtract it from OTB, and flag any order you can still cancel or push back.
- Before the next order: BOM and landed cost (mistakes 2 and 7). Strip aged stock out of BOM and recalculate cost OTB with freight and duties included.
- Monthly from now on: reforecasts and category plans (mistakes 5 and 9). Close each month against plan by category and adjust the next receipt.
- Before next season: sizing and review (mistakes 1, 4, 8 and 10). Run the season-end review, set stock-to-sales from your history and size reorders from sell-through.
If you fix only one, fix the on-order log. In my view it's the cheapest repair on this list, and it protects cash you haven't spent yet.
The warning signs often show up before the season-end numbers do. These signs your cash is trapped in inventory are a useful check between reviews.
All 10 Open-to-Buy Mistakes at a Glance
Every dollar figure below comes from the illustrations above and describes a hypothetical store.
| # | Mistake | What it does to cash | Illustrative cash at stake | Fix |
|---|---|---|---|---|
| 1 | Reordering last season's buy | Repeats last season's leftovers | $5,320 at cost | Size reorders from sell-through |
| 2 | Counting dead stock and shrink as BOM | Plan looks covered while aged stock holds cash | $8,910 at cost | Plan on sellable BOM and give aged stock an exit plan |
| 3 | Forgetting what's on order | New orders land on money already promised | $19,800 at cost | Subtract on-order at retail and log cancel dates |
| 4 | Setting EOM stock by feel | Inflates every month's receipts | $9,000 at cost | Set stock-to-sales from your own history |
| 5 | Keeping the plan after a sales miss | Missed sales turn into carryover | $4,905 at cost | Reforecast monthly and cut the next receipt |
| 6 | Committing the season at the show | Reorders land on top of a full plan | $6,000 over plan | Hold an in-season reserve |
| 7 | Budgeting at invoice cost | Freight and duties overrun the budget | $2,479 over budget | Calculate cost OTB on landed cost |
| 8 | Buying to price breaks | Extra units sit for weeks | $691.20 extra cash out | Run the break-even first |
| 9 | One store-wide number | Overages hide behind shortages | $5,400 at cost | Plan by category and location |
| 10 | Skipping the season-end review | Next plan repeats the same errors | About $11,300 at cost | Review every line before replanning |
Start Here: Four First Steps This Week
- Today, export your open purchase orders and list them by delivery month at retail and at cost. Subtract them from this month's and next month's OTB.
- Run an aging report and pull every item with no sales in your chosen window out of BOM inventory.
- Pull last season's units received and units sold by category, and calculate sell-through for each one.
- Put a dollar figure on the stock already in the back room with the free trapped-cash estimate. For the SKU-level view, connect your store data to a free workspace. This directional questionnaire gives a benchmark range; use a supported connection or reviewed item-level upload for SKU-level analysis.
The next plan is only as good as the count it starts from. Get the number for what's already sitting in the back room, then write the purchase order.
Frequently Asked Questions
What are the biggest open-to-buy mistakes?
The biggest open-to-buy mistakes commit cash before sales justify it. Ignoring stock already on order, counting dead stock as BOM inventory and holding a plan after sales miss do the most damage. Copying last season's buy and skipping the season-end review keep those errors repeating.
How do you calculate open-to-buy?
Retail open-to-buy equals planned sales plus planned markdowns plus planned end-of-month inventory, minus beginning-of-month inventory. Cost open-to-buy is that figure multiplied by one minus the initial markup percentage. Subtract stock already on order at retail to get the open-to-buy still available to spend.
What does negative open-to-buy mean?
Negative open-to-buy means a store has already received or ordered more inventory than its plan can absorb for that period. The fix is to cancel, delay or shrink open orders before adding anything new, then check whether sales are running under plan.
How often should a small retailer update its open-to-buy plan?
A small retailer should update its open-to-buy plan at least monthly, comparing sales, markdowns and receipts with plan after each close. Update it again before any trade show or large order, because that's when cash gets committed fastest.
Should open-to-buy be calculated at retail or at cost?
Open-to-buy is planned at retail and spent at cost. Calculate retail open-to-buy from the sales plan, then convert it with the cost complement. Use landed cost, including freight and duties, so the budget matches the cash that leaves.
Can a single-location store run open-to-buy without planning software?
A single-location independent store can run open-to-buy in a spreadsheet with monthly sales, markdowns, stock levels and open orders by category. The inputs matter more than the tool: an accurate BOM figure, a current on-order list and last season's sell-through.
How does Cash Margin Partners help with open-to-buy planning?
Cash Margin Partners shows the cash last season's buy left in slow-moving and dead stock, so the next plan starts from evidence. CMP connects read-only to Shopify, Square or Lightspeed Retail X-Series, or reads a spreadsheet upload, and never writes to your store. The software is free, and Lightspeed availability depends on workspace eligibility. Direct availability depends on production launch status and workspace eligibility; compatible item-level exports remain available after column review.