Prepare Your Inventory for Black Friday & Holiday Sales

Black Friday and the holiday season can make or break your year. For many Shopify merchants, November and December account for 30-40% of annual revenue. But here's the catch: the decisions that determine whether you capture that revenue or miss it are made weeks — sometimes months — in advance.

Running out of your top sellers on Black Friday is painful. But overstocking products that don't sell and sitting on excess inventory through January is equally costly — and if it sits long enough, it becomes dead stock. The goal is to find the balance, and that starts with preparation.

Start Planning 8-12 Weeks Before Black Friday

If your average supplier lead time is 3-4 weeks, you need to place your holiday orders by early October at the latest. That means your planning should start in September.

Here's why the timeline matters: you're not just accounting for lead time. You also need time to analyze your sales data, decide on quantities, negotiate with suppliers (who are also getting slammed with orders), and build in a buffer for delays. Shipping delays are common heading into Q4 as every retailer is restocking simultaneously.

Analyze Last Year's Holiday Data

Your best predictor of this year's holiday demand is what happened last year. Look at:

• Which products sold the most during November-December
• Which products ran out of stock and how much revenue you estimate you lost
• Which products you overstocked and had to discount in January
• How much demand increased compared to your average monthly sales

If you're using Sensible Forecasting, open the product detail view and compare sales rates across different periods. The 90-day view heading into the holidays will show you the ramp-up in demand, while the 30-day and 14-day views will show you the most recent acceleration.

Adjust Your Forecasting Settings for the Season

Your everyday forecasting settings probably won't be aggressive enough for Black Friday. Here's what to adjust:

Switch to a Shorter Sales Period

If you normally use the 90-day weighted average, consider temporarily switching to a 30-day or even 14-day sales period as you approach the holiday season. This makes your forecasts more responsive to the recent uptick in demand rather than being anchored to slower summer months. Learn more about how to choose the right sales period for different scenarios.

Increase Your Days of Stock

During normal months, covering 30 days of demand might be enough. For the holiday season, consider increasing this to 45-60 days. This gives you a larger buffer and reduces the risk of running out mid-season when supplier restocking will be slow.

Add Extra Safety Stock

Supplier delays are more common during Q4. If you normally keep 7 days of safety stock, bump it up to 14 days for your top-selling products. The cost of holding a bit more inventory is far less than the cost of being out of stock during your highest-traffic week. For a detailed breakdown, see our guide on what safety stock is and why you need it.

Review Lead Times

Ask your suppliers directly: "What will lead times look like in October and November?" Many suppliers slow down or get backed up heading into the holiday season. Update your lead time settings in Sensible Forecasting to reflect reality, not the optimistic estimates from quieter months.

Prioritize Your Top Sellers

You can't stock up on everything equally. Focus your holiday preparation on the products that actually drive revenue.

A simple rule: your top 20% of products likely generate 80% of your revenue. These are the products where a stockout hurts the most and where carrying extra inventory is worth it. For the long tail of slower-moving products, your normal forecasting settings are probably fine.

In Sensible Forecasting, sort your products table by sales rate to quickly identify your top performers. These are the ones that deserve the most attention in your holiday planning.

Place Orders Early — Then Place a Second Order

Instead of trying to guess the exact right quantity in one giant order, consider a two-order strategy:

1. First order (8-10 weeks out): Order enough stock to cover your forecasted demand through Black Friday, plus safety stock. This is your "base" order.
2. Second order (3-4 weeks out): By now you'll have more recent sales data showing how demand is trending heading into the season. Place a top-up order for your fastest-moving products.

This approach gives you the safety of an early order with the accuracy of more recent data. It's much less risky than a single all-or-nothing order placed months in advance.

Plan for the Post-Holiday Period

The holiday rush ends, but inventory decisions don't. Think ahead about:

• Return rates: Depending on your product category, 10-30% of holiday purchases may come back. Factor this into your overstocking risk.
• January clearance: If you do end up overstocked, have a plan ready — bundles, discounts, or marketing campaigns to move excess inventory before it becomes a cash flow problem.
• Resetting your settings: Remember to switch your forecasting settings back to normal after the holiday season. A 14-day sales period that worked great in December will give you wildly inflated forecasts in January as demand drops.
• Exclude promotional periods from your forecast: This is critical. If you ran major Black Friday or holiday discounts, those inflated sales numbers will skew your forecasts going forward. In Sensible Forecasting, use the Exclude Sales setting to remove specific promotional date ranges from your sales data. This way, the app calculates future demand based on your normal baseline sales — not the spike from a one-time 40% off sale. Without excluding these periods, you'll end up ordering far more inventory than you actually need in the months that follow.

The Holiday Preparation Checklist

Here's a quick summary of what to do and when:

September (8-12 weeks out): Review last year's holiday data. Identify top sellers. Adjust forecasting settings (shorter sales period, more safety stock, higher days of stock). Place your first round of purchase orders.

October (4-8 weeks out): Monitor early sales trends. Confirm supplier lead times. Place second-round orders for top sellers that are trending strong.

November (0-4 weeks out): Focus on monitoring, not ordering (it's too late for most suppliers). Use Sensible Forecasting's daily or weekly inventory reports to track stock levels during peak. Snooze products you can't restock.

December-January (post-peak): Switch forecasting settings back to normal. Use Exclude Sales to remove promotional periods from your forecast data. Assess overstock positions. Run clearance if needed.