Guide to Seasonal Forecasting For Your Shopify Store

Running a business has its fair share of ups and downs – and even more so if your sales tend to be more seasonal. Activity can swing wildly depending on the time of year, and if you’re not prepared, those quiet spells can sting. But the good news? With a bit of forward planning (and a few smart habits), you can ride the waves rather than being knocked over by them.

Here’s a straightforward guide to help Shopify store owners like yourself forecast for seasonal peaks and troughs – so you can make more confident decisions, manage your stock better, and avoid getting caught off guard.

Why forecasting matters

If your shop sees big boosts around Christmas, summer holidays, or any other seasonal period, forecasting isn’t just a “nice to have” – it’s essential. Without it, you’re more likely to over-order (and get stuck with unsold stock), under-order (and lose out on sales), or stretch yourself thin during quieter times.

Forecasting gives you a clearer picture of what’s coming, so you can:

• Order an adequate amount of stock
• Plan staff hours and marketing in advance
• Keep your cash flow in check
• Reduce stress (always a win)

Start with last year’s sales

The best place to start? Looking back. Your previous Shopify sales data is a goldmine. Dive into your analytics and pull out figures from the same season last year. Pay attention to:

• Total sales volume
• Bestsellers and slow movers
• Marketing campaigns that worked
• Customer behaviour (e.g. average order size, top regions)

If you’ve been trading for a few years, even better – patterns will be easier to spot. But don’t worry if you’re newer to the game. Even one season’s worth of data can help guide your next steps.

Factor in what’s changed

Last year’s data is your starting block, not the full picture. Think about what’s different this time round:

• Have you added new products?
• Are there economic factors at play? (Cost of living, interest rates, etc.)
• Did you improve your website or invest in ads?
• Are competitors doing anything new or noisy?

These changes can skew your numbers – up or down – so it’s worth adjusting your expectations based on what you know has shifted.

Consider going digital for forecasting

When it comes to planning and managing your stock, it’s well worth investing in proper inventory management software to help you automate forecasting.

These tools don’t just keep track of what you have in stock across all your products – they can also link up with systems like QuickBooks Online and Shopify. That way, your stock levels update automatically, so you’ll know straight away if you’re close to running out of something.

Shopify recommends the app Stocky, in particular. It’s designed to give you better visibility of your supply chain and helps you figure out what to reorder based on how products are performing and seasonal trends.

What if you get your forecasting wrong?

First of all: don't worry. Shopify itself says: "Nearly all forecasts are incorrect."

Their advice instead is not to aim for perfect accuracy, but to be "close enough that there's enough inventory and resources to efficiently fulfil your orders", with a recommendation to forecast with a 10-15% margin of error.

It's also important to remember that what you get wrong this year, you'll likely get right (or at least more right) next time around. Succeeding in business isn't a linear path, but one marked by trial and error.

How to plan for peaks

Christmas, Black Friday, the summer holiday shop – there are lots of key shopping seasons throughout the year, and your business may see a few across the calendar.

Data first

When it comes to planning for a busy shopping period, start with – as we've mentioned before – your store data, and namely, the products that sold the most during the last peak. You might think to order more of your bestsellers this time around, and possibly order them earlier to avoid supplier delays.

Shopify recommends trying to "keep your minimum inventory at about 70% of your maximum inventory level for your busy season."

Review your website

Next, you should give your store a once over – it's about to become a star attraction. Make sure product descriptions are clear, images look good, and checkout is smooth on mobile and desktop. Add delivery info and consider back-in-stock alerts to improve the customer experience even more.

Plan your marketing

Then, nail down your marketing strategy, including emails, social media posts, and any promotional activity like sales or discounts – this may be the best opportunity you have all year to make a big splash with your customers. Think of it as a bit of a power-up to your already speeding racer!

Segment audiences

You should also consider segmenting your audience, too, so that those who regularly purchase more during Christmas, or autumn, or some other busy shopping period get, for example, first access or more tailored messaging.

Prep your customer support

Have clear FAQs ready, set expectations on response times, and consider automating common replies. A bit of planning now means you’ll handle the rush with far less stress.

How to plan for troughs

Quiet periods might feel like time treading water, but they can offer a few advantages, too. Start by reviewing your data to see when and why sales typically dip to help you prepare realistic targets and cash flow plans.

Make store improvements

Then, when your slower spell arrives, use the surplus time to improve your store. When a store is go, go, go, there is a rarely a moment to look at the big picture, or get a good refresh in, so think new product photos, tidying up descriptions, creating blog posts, or working on your SEO. You might also consider adding new products or bundles to tempt returning customers.

Plan consistent, lower-cost marketing

Of course, you're also likely to want to make efforts to entice customers, even if it may not be the key time of year. Think discounts, sales, new products, special competitions, and carefully-considered marketing.

Focus on returning customers

We understand this probably won't be a time to splurge on big influencer collaborations or motorway billboards, so we would recommend narrowing your marketing to focus on loyal customers, rather than a broad scope.

And why is that? Because they convert better.

According to Klaviyo "the average ecommerce store earns 41% of their total revenue stream from only 8% of their customers" and that "repeat customers spend three times as much as first-time customers." Therefore, marketing tactics which target these repeat shoppers – like subscriber-only sales, fan-first products, or a new replenishment email automation – could make the most impact for the least expense.

Remember this is temporary

Above all, stay positive. Lulls are a normal part of retail. Treat them as breathing space to strengthen your business, so when the next rush comes, you’re more than ready for it.

Final Thoughts

Forecasting isn’t about predicting the future perfectly – it’s about being better prepared. As a Shopify store owner, you’ve already got the tools and data you need. With a bit of time and attention, you can get ahead of the seasonal swings and run your business with more confidence and calm.

And remember: what you learn this season will only make next season easier.

In the meantime, if need some advice on setting up a Shopify store, or some guidance on making it work for you, you can always reach out to us. We've built over 200 Shopify stores and know there is no one-size-fits-all approach, so get in touch today - we're happy to help.

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