Regardless of the industry or sector, sales often undulate between peaks and troughs rather than following a consistent linear pattern throughout the year. 

While sales and conversions fluctuate on their own accord due to factors marketers can’t easily predict, one cause of change that marketers can predict is seasonality. 

Whether you’re in the northern or southern hemisphere, societies and environments are shaped and influenced by the seasons. 

Each season comes with its own events, character, cultural influences, etc. Christmas is an essential example, with some retail businesses making over ¼ of their total yearly sales in just one month. Many businesses hold back much of their yearly marketing budgets solely for Christmas, where they go all out in an effort to make windfall profits. 

Seasonality also applies to topics or niches that expand and contract with different seasons. Gardening is a key example, we can see from the Google Trends graph below that interest in gardening grows through early spring and declines through late summer and winter. 

What is seasonality?

Would you put out a Christmas advert in summer? Obviously not (in the Northern Hemisphere, anyway). 

Christmas belongs to a specific season - usually winter in the countries that celebrate it - which totally influences sales and marketing. However, while Christmas is boom time for retail, services businesses may see the opposite - sales decline as people push their money into retail. 

Seasonality is shaped by calendar events 

This is an obvious example of how seasonality affects markets, but seasonality goes much deeper than that. From Christmas and Black Friday to Easter, Hanukkah, and Thanksgiving, the calendar is littered with events that marketers can take advantage of. 

In addition, the seasons themselves lend themselves to different products. For example, gardening is a warm-weather activity, whereas interior DIY is perhaps a rainy day or winter activity. 

Marketers have to respond to calendar events, harnessing them in such a way that links to their products and their customers. 

Seasonality is shaped by preferences 

For other niches, seasonality is less obvious. For example, the climbing season often peaks before and after summer, with limited activity in high summer because of the heat (depending on where you are). Some seasons are very narrow - the Everest climbing season is pretty much just April and May each year, for example. 

Marketers have to understand preferences, optimize campaigns for when a particular activity is hitting its peak, and leverage other strategies during the off-peak. 

Seasonality is shaped by local, regional, national, and global events 

Seasonality applies outside of routine calendar events, too. For example, the coronavirus pandemic saw a massive increase in grocery delivery, subscription product, furniture, home improvement sales, and mass adoption of Zoom, Microsoft Teams, etc. This reflected that people were staying in, working from home, and diverting spare cash to different things other than holidays. 

One-off or transient effects create their own brand of seasonality. Coronavirus is the archetypal example of this - it profoundly affected trends across practically every industry. 

Seasonality is shaped by seasonal produce 

Finally, seasonality is shaped by the product itself. Some products aren’t available off-season or are more expensive to source. 

This is often the case with seasonal fruit and vegetables, but even some raw materials like timber are sensitive to seasonality. Therefore, marketers must know how their products interact with industry-specific trends that affect supply and demand in these situations. 

What isn’t seasonality?

Seasonality could be considered predictable year-on-year, though that isn’t the case with some wide-scale events like coronavirus. Macroeconomic impacts are generally not considered seasonality, and shouldn’t be conflated with it. For example, mass unemployment may cause long-term teams that aren’t linked to any sort of seasonality. 

Marketers face the challenge of delineating seasonality from other influential factors. This can be fairly straightforward or highly complex.

How to measure seasonality

Most businesses have some seasonality, whether it's higher sales during sunny weather, more revenue near payday, or lower sales after the weekend. Major holidays and government holidays also tend to impact sales, increasing B2C business activity or hurting B2B. 

The impact of seasonality is typically accounted for with dummy variables for holidays, specific days of the week or month, or major holidays. It's also possible to incorporate weather data to see if there's an effect. Unfortunately, these variables are commonly entangled with others, causing colinearity, because marketers typically spend more and run promotions around holidays.

Measuring how seasonality affects your own business means analyzing your sales and conversions. Discovering seasonality in your products might be extremely straightforward - you might make practically no sales all year until November and December, when your sales shoot through the roof. 

However, you can see how complex seasonality gets if you’re selling multiple products in different product categories and through different channels to different locations. In this situation, it’d be wise to group products into related categories to show seasonal sales variations relative to each product. 

The more data you have from more years, the stronger your seasonality data will be. It’s often a case of plotting your sales or conversions data on a graph, in one of the following ways: 

• A run sequence plot, or a run chart, is a graph that displays data in a time sequence. Multiple variables, e.g., products, can be plotted for easy comparison. 
• Seasonal plots are similar, and are excellent for comparing different years or time periods. 
• Autocorrelation plot (ACF) identifies seasonally shifting variables relative to each other.

Seasonality is also incorporated into marketing mix models, enabling marketing strategies to be modeled and predicted alongside seasonality and other external factors. By incorporating seasonality into a MMM, marketers can avoid assessing their marketing performance in a vacuum.

Once seasonality data has been pulled from sales and marketing channels, time series analysis can predict future trends based on past history. This makes it possible to extrapolate and predict the impact of future marketing strategy without neglecting the role of seasonality. It also makes it possible to simulate the impact of different marketing strategies for different seasons. 

How to discover seasons

Discovering seasonality is not as simple as many assume. 

While most seasonal vectors are obvious, e.g., spring, summer, fall, winter, Christmas, Thanksgiving, etc, there are many other small niche seasons or celebrations outside one’s culture. 

For example, a drop shipper might identify climbing gear as an outstanding product category with high demand, but what if they have no idea about the climbing season? As a result, they might buy in a load of stock right as the climbing season winds down and sit on that stock all year, failing to optimize their ad spend, campaigns, etc. 

It’s essential to explore your niche, sector, or industry using Google Trends. Google Trends provides time and location-specific data on search trends. These are given a relative score from 0 to 100, with 100 being peak interest. Looking at Google Trends data reveals peaks and troughs for topics or keywords. 

For example, in the graph below, “gift for her” peaks at two distinct periods of the year - Valentine's day and Christmas. 

The hiking season gradually increases through spring and summer, declining in fall. The graph below also shows that interest is strongest in Colorado, Utah, and Vermont, home to many world-famous hiking hotspots. 

Here’s another interesting one: interest in rings shows a moderate increase at Valentine's Day, but necklaces show a weak correlation. This tells you that Valentine's Day seasonality affects some products more than others. 

Trends provide a powerful mine of data covering search trends and seasonality, which are closely linked. 

View this article for more practical tips on using Google Trends as a marketer. 

Benefits of seasonal marketing

Seasonal marketing is not optional. Increased interest means increased opportunities. On the flip side, declining interest signals ventures into other strategies. 

For example, it might be necessary to diversify an eCommerce business to counteract the extreme seasonality of some products. Some overhead costs - e.g., web hosting, subscriptions, hiring, etc., - are often very consistent throughout the year. That may not be compatible with an overly seasonal business model. 

Here are the chief benefits of seasonal marketing: 

Capture interest and excitement 

When people are excited or interested in something, they tend to let their guard down and allow their impulses to take over. 

This increases buying activity, especially in product categories dominated by impulse buying. Some 1 in 3-holiday purchases is made by impulse, according to Google. Additionally, more than 30% of people shopped with a brand they weren’t familiar with. 

Capturing that excitement is excellent for new businesses that can quickly build a growing customer base. This also provides opportunities for retargeting when the season has passed. 

Increasing brand awareness

Tying in with the above, brands can use seasons to enhance brand awareness. By displaying a strong understanding and affinity with the season, it’s possible to tap into niche segments. For example, a gardening business should demonstrate strong knowledge of what plants need to be planted at what part of the season. In addition, illustrating seasonal knowledge builds rapport and strengthens bonds with customers. 

Boost sales

This is an obvious one. The goal of seasonal marketing is to make more sales. More interest, traffic, and cash flowing into certain product categories or niches mean more sales. This isn’t just the case for large-scale seasons, such as Christmas, but it also applies to smaller niche-specific seasons. For example, marketing climbing gear ahead of the peak climbing season. 

How to create seasonal marketing campaigns

Creating effective seasonal marketing campaigns relies on knowledge, data, and timing. The goal is to transform seasonality into a profitable angle in peak and off-season seasons. 

1: Know your data

Firstly, it’s best to look at your own sales on conversions data. Modeling your data using a marketing mix model can reveal seasonality's impact, enabling marketers to predict how ROI might increase or decrease with marketing spend depending on seasonality. 

Secondly, if you collect customer data, you’ll need to look at that to reveal where your customers are from, their demographics, etc. Again, Google Analytics’s User tab is excellent for revealing interesting data about customers or website visitors, including their affinity groups. This data provides a starting point for conducting trend and seasonality analysis. For example, your audience might share common interests, which enables you to assess those interests for any seasonal dynamics.  

2: Prepare marketing calendars to accommodate seasonality

Next, you’ll need to plan your marketing strategies well in advance. That includes content marketing, PPC, influencer marketing, etc. For PPC, you’ll need to prepare your keywords well in advance, especially as your campaigns will need to be approved. Moreover, if you’ve paused poor-performing keywords, then go through those ahead of the season and analyze whether they went cold because of being off-season or some other reason. 

In terms of content marketing, prepare blog posts and social media well ahead of the season. This ensures that your seasonal content plan will flow with minimal work when the time comes. If you’re marketing for a season you’re not familiar with, do your research and ensure you get all the details right - you don’t want to expose your lack of knowledge to your customer base!

Finally, if you’re planning seasonal products, make sure you get those sorted in good time. For example, if you order tons of Christmas products for Amazon FBA but fail to get them to the warehouse and marketed in time, that’s a big waste of money!

3: Prepare discounts and sales

It’s customary to offer sales, discounts, and other holiday deals. This means adjusting your prices and analyzing profit margins and ROAS. Consider a deal countdown “10 days until the big sale!” to build tension. 

Ensure you place sales banners where people can see them, at the top of your website, or on a landing page. 

4: Focus on seasonal SEO

If you’re writing seasonal blog posts or social media content, do seasonal SEO research to reveal topical keywords. For social media, research seasonal hashtags. If you’re selling products on a site that uses tags, e.g. Etsy, then research seasonal hashtags to add to your listings.

5: Increase ad spending

Ads should convert better with seasonal demand. As such, it’s wise to raise budgets. Automated advertising should increase ad spend with an increase in ROAS. Changing ad copy and images to reflect seasonal changes is also necessary. Finally, consider automating seasonal keywords, so the poor performers are stopped while the budgets for good performers increase. You can do this via seasonality adjustments in Google Ads.

Summary: Seasonality

Seasonality is simple in principle, but it becomes much more complex when you drill down into its various nuances. 

At the macro level, seasonality refers to predictable year-on-year changes and transitions. Winter, summer, spring, and fall are obvious, then you have large-scale events such as Christmas, other cultural celebrations, niche-specific celebrations, and events, etc. But, in the end, seasonality isn’t just about predictable events and transitions as much as it’s about what’s ‘in season’. 

For obvious reasons, face masks were very much ‘in season’ throughout the COVID19 pandemic. This is (hopefully) not a typical season, but it still somewhat falls under the category of seasonality. However, true seasonality shows similar characteristics year in, and year out. 

Seasonality and search trends work together in tandem. So, while seasonality might reflect in your sales and marketing data, it’s essential to look at how seasons connect to trends to understand what’s going on.