Strength in numbers: is 9 your marketing secret weapon?

Mighty number nine, from price psychology to 9-enders

One of the joys of the copywriter life is the chance to noodle over individual words. Or in this case, numbers. Specifically, number 9.

So what makes the number 9 cast a spell on our psyche?

First things first - numbers are a copywriter’s secret weapon. Numbers, stats and data make abstract ideas feel more concrete. It’s easier for us to process concepts if they have numbers attached to them.

Doesn’t ‘nine days ago’ sound instantly more credible than ‘recently’?

So what is it about the number 9?

Here are three lightbulb concepts around the number 9 for marketers -

1. Price psychology

2. Word associations

3. 9-enders

The number 9 & price psychology

The science of price psychology explores how different pricing strategies influence buyer behaviour.

Numerous studies have demonstrated the effectiveness of using nines strategically in pricing.

In fact, the practice of ending prices with the digit nine is built on psychological insight known as "charm pricing".

Charm pricing number 9

Here’s the theory - a product priced at £49 may be perceived as significantly cheaper than a product priced at £50, despite the minimal difference in cost.

We can attribute this to the psychological principle of Left-Digit Bias.

The Left-Digit Effect

The Left-Digit Effect suggests that people tend to focus on the leftmost digit when they interpret numerical information like price.

Left-digit anchoring means that the digit on the left acts as a reference point when buyers evaluate price. By ending prices with a nine (for example £49 instead of £50) you may anchor customers' perceptions at the lower left-digit (4 instead of 5).

This makes the price itself feel more favourable than the simple £1 difference.

This is why products priced with nines tend to experience higher sales volume and improved price perception.¹

If you’re interested in price psychology, try this on for size too - the fewer syllables in a price, the smaller we perceive it to be. I’ll investigate the link between syllables and copy psychology in another post soon.

Positive associations & the word nine

I’ve written before about how copywriters can use words (and even parts of words, such as phonemes) to prime buyers to feel positive associations.

Priming happens when we’re subtly exposed to certain words that trigger feelings we aren’t consciously aware of.

That’s why the word nine might just be an important linguistic weapon.

Let’s think of the common associations we might make when we come across the word nine -

• Nine months - the length of a typical pregnancy.

• Cloud Nine - symbolises euphoria.

• Dressed to the nines means styled up to the max.

• The whole nine yards means to make maximum effort.

• The cat with nine lives is an analogy for the uncanny ability to survive.

• A stitch in time saves nine suggests that timely action prevents bigger problems.

• Nine times out of ten is an important priming phrase associated with high probability or virtual certainty.

Positive primes - the Whole Nine Yards

In fact, in terms of English phrases in common use, I’m pushed to think of many where the word nine comes primed with negative associations.

Maybe the Nine-Day Wonder is one example that proves the rule? It refers to a person or concept that appears in the limelight briefly, only to be forgotten.

Fresh starts & 9-enders

Have you ever considered how your products or services might appeal to someone at a milestone moment in their life?

Meet the 9-enders, a powerfully-motivated demographic.

Marketing to 9-enders means you target individuals whose age ends in the number nine (for example, age 29, 39, 49 and so on).

9-enders are more likely to do all kinds of interesting things

So why single out the 9-enders?

This application of marketing psychology is based on the idea that, when people approach a new decade in their lives (around a milestone birthday), they may experience a heightened sense of reflection, evaluation and transition. Alter and Hershfield² found that 9-enders in the last year of a decade tend towards some behaviour more than other people in the same decade.

Among other things, 9-enders may be more likely to run a marathon, get married, change jobs, seek out bucket-list experiences or buy luxury items.

This tendency could be linked to the Fresh Start Effect and its relationship to our behaviour and habits.

Three reasons to consider 9-enders in your marketing.

1. A new decade just feels significant. Perhaps your product or service is a tool to help 9-enders embrace the next decade of their life?

2. 9-enders are also likely to engage in self-reflection around their milestone birthday. They might evaluate their achievements so far, as well as their goals and hopes for the future. Can you offer personal growth, self-improvement or a bucket-list experience? Smart positioning can be powerful in that case, if your messaging aligns with 9-enders’ evolving desires.

3. The transition to a new decade often sparks desire for renewal or reinvention. Help 9-enders explore new interests or hobbies. They may also be more likely to consider significant personal transformations, whether they’re physical, cerebral or spiritual.

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I fix business messaging using copywriting psychology and write about it here every week. You can find out more at Virtual Gold Dust.

1. Schindler, R., & Kirby, P. (1997). Patterns of Rightmost Digits Used in Advertised Prices: Implications for Nine-Ending Effects. Journal of Consumer Research.

2. Adam L. Alter & Hal E. Hershfield. (2014). People search for meaning when they approach a new decade in chronological age. https://www.pnas.org/doi/full/10.1073/pnas.1415086111