The 80/20 rule in sales: test it on your client list, then decide where your hours go

The 80/20 rule is the idea that a small share of causes produce most of the results. In sales, people apply it to three things: a few clients bring in most of your revenue, a few activities lead to most of your deals, and a few reps close most of the team's business.

It's also called the Pareto principle. Investopedia's explainer traces it to the Italian economist Vilfredo Pareto, who described in 1906 how unevenly wealth was spread in Italy. Joseph Juran later applied the same idea to quality control in manufacturing, and it spread into business from there.

The same explainer makes two points worth keeping. The rule is a precept, not a mathematical law, so your split might be 70/30 or 90/10. And deciding to focus on the few doesn't mean the rest don't matter.

That's the right way to use it in sales. It's a prompt to go and check your own numbers, not a fact about your business.

You need last year's revenue by client. Your CRM, your invoicing tool or a spreadsheet will do.

1. List every client who paid you in the last 12 months, with what they paid.
2. Sort from biggest to smallest.
3. Add up a running total down the list.
4. Find the point where the running total passes most of your revenue, and count how many clients sit above it.

Then look at the top group. What do they have in common? Same industry, same size, same way they found you, same person who sold to them? That pattern is worth more than the split itself, because it tells you who to look for next. The ideal customer profile entry covers how to write it down.

The second test is about your time. Look at the deals you signed in the last six months and ask where each one started: a referral, a cold call, an event, a website enquiry, an old client coming back. Then look at where your hours went.

Tom shouldn't stop cold calling on the strength of that. Cold calls still led to five deals, and they're the one source he can turn up on a slow week. But he should move a couple of hours from cold calling to referral asks and check the result in a month. The sales activity metrics guide covers which activities to log so you can run this test at all.

Once you know your split, four moves follow:

• Protect the top clients. Put their reviews in the calendar first, and make sure a person looks after them. They're also your best source of referrals.
• Drop or batch low-value work. If small one-off clients take a lot of admin, give them a simpler process, or handle them in one block a week.
• Look for more clients like the top group. Use the pattern you found, not just the size of their spend.
• Put more hours into the activities that lead to deals, and fewer into the ones that just fill the day.

Two things not to do. Don't ignore the middle of your list. Some of today's mid-sized clients will be next year's top ten if they're looked after. And don't stop finding new prospects. Every client in your top group was a new prospect once.

Managers often apply the rule to reps: a few top performers close most of the business. That may well be true on your team. The trap is what comes next.

SalesScreen argues that treating the rule as a management plan is outdated. When managers give most of their coaching, recognition and attention to the top few, the middle of the team gets less help, and the gap the rule described gets wider.

The middle of the team is usually where coaching moves the total most. A top rep who's already at their best has less room to grow than a steady rep who's one habit away from a much better month. Spend your 1:1 time where it can change the number, and use a win rate calculator to see which reps convert well but don't have enough at the top of the pipeline.

• One big client isn't a strategy. If your top client leaves, a revenue split that looked efficient becomes a problem. If one client is a large slice of your year, find more like them before you need to.
• Last year's top clients aren't next year's. A split from one year can reflect one lucky deal, so check two years if you have them.
• A big client who takes a huge amount of your time might be worth less than their revenue suggests, because revenue isn't profit.
• A deal that "came from a referral" may also have needed three follow-up calls and a meeting. Crediting only the first touch undervalues the rest of the work.
• New reps and new markets won't fit. There's no history yet to rank, so the rule tells you nothing until there is.

• Investopedia, The 80-20 rule (aka Pareto principle): Vilfredo Pareto and wealth in Italy in 1906, Joseph Juran and quality control, the rule as a precept and not a law, read 28 September 2026
• SalesScreen, The 80/20 rule in sales is outdated and what to do instead: the argument against using the rule as a management plan, read 28 September 2026