Customer Relationship Management

How to increase sales with your existing customers - sales expert plan

Jonathan Hubbard
Jonathan Hubbard
March 1, 2024

If you want to increase sales, the best place solution isn’t casting the net in search of more customers: use your existing customers instead. However, while this sounds simple on paper, getting more sales from existing customers can be like getting blood from a stone: unless you have the right plan.

We spoke to Ian Cartwright, a sales author and consultant with over 30 years experience to discover his technique to growing sales revenue. The result? Use your existing customers!

Listen to the video below to hear Ian’s technique for increasing sales with existing customers, or read our breakdown.

An expert’s plan for increasing sales with existing customers

Know your existing customers’ potential

Pareto principle in sales
Pareto in sales: 20% of effort yields 80% of sales results

Knowing where to do it is really like polishing what you've got, and hopefully, you have got some way in which you categorize your customers. It's about understanding - and Pareto principle really applies - that typically 80% of your business will come from 20% of your customers. 

Before you can polish your existing customers and increase sales, you’ll need to understand each customer’s significance to your business, and their growth potential. 

One of the best ways to do this, Ian explains, is to categorize your customers: in our case, that’s Platinum, Gold, Silver, and Bronze. From here, you’ll need to decide the criteria a customer must meet for each tier. This could be based on how much business they give you, their average spend, or their growth potential.

By doing this you're making sure that you're actually following the money and not chasing unicorns: it's a phrase a customer reflected back to me because he was spending a lot of time on people who ended up being Bronze categories, because he thought they might be good, but he hadn't been through the process to work it out. 

What about timeframe? Ian recommends you use customer sales data over 2-3 year to build a detailed picture of customer trends, however you can use software to identify these trends for you quicker. Using sales data will show you why an existing customer has grown, or why they flatlined: information you can use to decide which customers you could increase sales with. 

Help your top existing customers achieve their potential

Once you’ve categorized your existing customers, and identified trends, you’ll need to put a plan in place for nurturing them. To start building this plan, ask the following questions:

Key account plan existing customers
Make a plan for nurturing your key existing customers

  • What sales activities can reps perform to connect and appeal to these customers? Catch-up chats? Personal emails? A casual event? Giveaways?
  • How often should reps be performing these activities? Once a day? Week? Month?
  • What’s the best way for you reps to communicate to these customers?
  • What can we do to show our top customers we love them and want to solve their problems better?

[once we’ve identified our top customers, we can] program objective activity to make sure that we are in front of them or reaching out to them the right number of times in the right places regularly. Being able to find a way to gather that information and share it within your team is really important. Because that means that across the team you can start replicating good practice which works: making sure that you are clear on who your top customers are and that you are really loving them. 

Your goal with this plan is to give sales reps the guidance and resources they need to start nurturing their top customers and realizing their growth potential. Jumpstart your planning with the key account plan template on Ian’s website.

Use your new understanding to jump on sales opportunities

We know who your Gold and Silver customers are: but are you getting all of their business? A really simple exercise to identify low hanging fruit here is to identify whitespaces. 

Whitespaces exercise crease sales
Get this template here.

Using their key account plans, your sales reps can now plot out what products your existing customers are buying: and make plans to fill the gaps. This is the ‘how’ of increasing sales among existing customers. Follow these steps:

  • Write down your top customers, up to 10.
  • Write down the products you sell- there could be 5, or 50.)
  • Map out which products each customer purchases.
  • For each customer who doesn’t buy all your products (e.g. ⅘) find out where they’re filling the gap.
  • Using your key account plan, make a strategy for securing that business.

By identifying whitespaces, your reps can capitalize on previously hidden opportunities to get more sales. As Ian says: “If you can really nurture those existing customers, make sure you're maximizing the amount of problems you're solving for them - you do that you'll get the revenue.”

BONUS: Sustain the momentum by building more sales off of existing business

By this stage, your sales team will be on the way to increasing sales among their existing customers. But what if that’s not enough? Ian has an answer for this too: grow mold. 

Grow sales with existing customers like mold
Good sales spore next to each other

My last little saying around knowing where to do it is grow mold. Mold grows and spores right next to each other. So does really good sales. So if you've got an existing customer who might be doing some business in an area really similar to where you'd like to grow the next piece of business, just replicate that.

Growing mold is about leveraging the strong relationships formed with existing customers to get referrals and contacts in related businesses. It’s simple for reps to ask customers "we've been doing some great business together, who else do you think I should talk to?”

When a strong relationship exists, Ian explains that these discussions can even turn existing customers into advocates. Additionally, reps can use these customers to generate low cost case studies, perfect as anecdotes for other customers, especially those who are being nurtured from Silver to Gold. 


Increasing sales among existing customers is all about nurturing the right customers, taking advantage of sales opportunities and leveraging relationships. Want more expert sales advice? Check out our upcoming sales expert webinars here.

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