Quick Answer
A lash demand forecast estimates how many units of each lash SKU a buyer expects to sell or consume during a defined period. Build it from ten inputs: clean SKU history, recent sales rate, stockout corrections, promotions, seasonality, launch status, channel plans, customer commitments, supplier constraints and forecast error. Forecast at SKU level, record assumptions and compare the forecast with actual demand on a fixed schedule.
Compare the forecast by exact SKU with the supplier's lash minimum order quantity, order increment, packaging minimum and usable-demand horizon before converting demand into a purchase quantity.
When a SKU becomes unavailable, complete a documented lash stockout root cause analysis before changing the forecast so demand, supply, inventory-record and stock-status causes remain separate.
Compare the forecast with a consistent lash sell-through rate by SKU so the next planning cycle can separate true demand change from stockouts, receipts and inventory-record differences.
The forecast is not the purchase order. It is the demand signal that later feeds lash safety stock, reorder timing and cash decisions. Start with the active range in the salon lash tray inventory checklist, then separate fast-moving core trays from slow or experimental variants.
What a Lash Demand Forecast Should Answer
A useful forecast answers a specific question: how many units of SKU X are likely to be required at location Y during period Z? “We need more C curl” is not a forecast because it does not identify the exact length, thickness, tray format, quantity, location or date.
The Shopify Help Center's inventory reports documentation explains that inventory reporting can show quantities sold, sell-through and inventory remaining at product-variant level. Those measures provide evidence for a forecast, but the buyer must still account for future events that historical reports cannot know.

The 10 Lash Demand Forecast Inputs
- Active SKU master. Forecast only controlled curl, thickness, length, color, fan and packaging combinations.
- Clean sales or usage history. Use consistent periods and remove duplicates, test orders and known recording errors.
- Recent run rate. Give appropriate weight to current demand rather than blindly averaging an outdated range.
- Stockout correction. A zero-sale week may mean no demand was captured because stock was unavailable.
- Promotions and launches. Record campaigns, bundles, academy classes and new-channel activity separately.
- Seasonality and events. Mark holiday, wedding, festival or local booking patterns supported by your own records.
- Channel and location plan. Separate ecommerce, distributor, academy and salon consumption where behavior differs.
- Committed customer demand. Identify confirmed wholesale orders without double-counting them in the historical baseline.
- Supply constraints. Note MOQ, production time, transit time and packaging availability without treating them as demand.
- Forecast error. Compare forecast with actual use and preserve the reason for meaningful variance.
| Input layer | Evidence | Decision it supports |
|---|---|---|
| Product | Active SKU and approved specification | What exactly is being forecast? |
| Demand | Sales, salon use and customer commitments | How much may be required? |
| Event | Promotion, launch and seasonal calendar | Why could the baseline change? |
| Supply | MOQ and replenishment lead time | When must purchasing act? |
| Review | Actual demand and forecast error | Which assumption needs correction? |

Build a Simple SKU-Level Baseline
Choose a consistent weekly or monthly planning bucket. For a stable SKU, a simple starting baseline can be the average demand from comparable recent periods. Do not combine unlike products: a 0.05 C curl mixed tray and a 0.07 D curl single-length tray serve different demand.
Example: a buyer records clean demand of 82, 91, 87 and 100 trays across four comparable weeks. The simple weekly baseline is 90 trays. If a documented promotion is expected to add 18 trays, the working forecast becomes 108 trays for that week. This is an assumption-based planning example, not a guaranteed result.
For volatile or newly launched SKUs, use a range:
- low case based on conservative conversion or usage;
- working case used for purchasing discussion; and
- high case showing exposure if demand exceeds plan.
Record the method and data window beside every result. A number without an audit trail is difficult to improve.
Correct History Before You Trust It
Historical sales can understate demand when the item was out of stock, hidden from the store, replaced by a substitute or constrained by channel limits. Mark those periods instead of treating every zero as genuine lack of demand.
Also separate one-time bulk orders, free samples, internal transfers, returns and inventory adjustments. Shopify notes that quantity sold and inventory adjustments are different measures in its reports. Reconcile physical counts when the system balance is uncertain.
Connect the forecast to the lash product specification sheet. If a curl, strip, tray card or box version changes, decide whether the old and new versions are one demand series or separate SKUs. Combining incompatible versions can create purchasing and fulfillment errors.
Add Future Events Without Double Counting
Create an event register with the event owner, dates, affected SKUs, expected unit impact and evidence. If a promotion already occurred inside the historical baseline, do not add it again unless the future event is incremental.
Customer commitments should be traceable to a customer, requested date and confidence status. Separate confirmed orders from enquiries. A distributor opportunity should not automatically become committed demand simply because the potential quantity is attractive.
For a new SKU with little history, use comparable products cautiously. Explain why the analogue is relevant, then update the forecast quickly after early sales. The lash inspection sampling plan can control product inspection, but it does not prove market demand; quality and demand evidence are different.

Link Demand to Lead Time, Not Just a Calendar Month
Microsoft's inventory forecast documentation describes a forward view combining expected demand and supply so planners can review projected changes to on-hand inventory. A lash buyer can apply the same principle in a simpler worksheet.
Map the demand forecast across the full replenishment window: internal approval, supplier confirmation, material or packaging preparation, production, inspection, transport and receiving. Use the lash production schedule to test timing assumptions with the supplier.
Do not shorten the recorded lead time merely to make the plan look feasible. If a promotion falls inside the replenishment window, the decision may require existing stock, an earlier order or a smaller campaign rather than an optimistic delivery assumption.
Measure Forecast Error and Improve the Next Cycle
At the end of each period, record forecast, actual demand, unit variance and percentage variance where the denominator is meaningful. Then assign a reason such as stockout, promotion variance, customer cancellation, late launch, data error or unexpected channel demand.
Review high-value and fast-moving SKUs more frequently than slow tail items. Keep the review practical: the purpose is to change the next decision, not to create an elaborate spreadsheet nobody maintains.
A forecast should trigger review when:
- actual demand repeatedly falls outside the agreed range;
- a core SKU stocks out or accumulates excess inventory;
- supplier lead time changes materially;
- a product or packaging revision is introduced; or
- a channel, market or customer commitment changes.
Frequently Asked Questions
What is a lash demand forecast?
It is a time-bound estimate of expected sales or consumption for defined lash SKUs. It should identify product, quantity, location, period, method and assumptions. It supports inventory and purchasing decisions but is not itself a purchase order or a sales guarantee.
How much sales history is needed?
Use enough comparable history to show a meaningful pattern, but do not apply one universal period. New, seasonal and frequently changed SKUs may need short review cycles and ranges. Stable products can use longer history if older data still reflects the current offer and channel.
Should stockout periods be included?
Flag them before calculation. Recorded sales during a stockout may understate actual demand because customers could not buy the item. Estimate any correction transparently and keep the original data visible rather than silently replacing it.
Should forecasts be made by curl or by individual SKU?
Operational purchasing should normally reach the controlled SKU level, including curl, thickness, length or mix, tray format and packaging version. A curl-level summary can help management, but it may hide shortages and excesses inside individual variants.
Is sell-through the same as demand?
No. Sell-through compares units sold with available inventory during a period. It is useful evidence, but future demand can change because of promotions, seasonality, stockouts, launches, channels or customer commitments.
How often should a lash demand forecast be reviewed?
Set a fixed cadence based on SKU speed, replenishment lead time and business risk. Fast-moving or promotional items may need weekly review; slower stable items may need less frequent review. Recheck immediately after a material demand, supply or specification change.
Next Step
Use the forecast to define a reasoned buffer and run the lash reorder review. If you need a supplier-ready plan, contact LASHMAITRE with your active SKU matrix, demand window, approved specifications and destination.
Turn Your Lash Forecast into a Supplier-Ready Plan
Share your active SKU matrix, expected demand window, approved specifications and replenishment timing with LASHMAITRE to prepare a practical wholesale order plan.