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Case study · Sales and marketing

A web form was creating duplicate contacts in the sales system. Now each person is there once.

The same person appeared twice, and one person's details were replaced by another's. We found why and fixed the one form that caused it.

Who
A small business with a sales and marketing team of five, using HubSpot as its sales system.
The problem
Leads from one web form kept creating duplicate contacts, and on shared computers one person's details replaced another's.
What we did
Found why the form behaved that way, changed it, and tested it with made-up submissions.
The result
Each person appears once with every submission recorded, and two people on one computer stay two people.
Time
Four days.
Get a price for something like thisThe service behind it

What was going on.

The sales team noticed the same person appearing twice in the sales system, and several companies sharing one website address. Then a salesperson found that a new form message had replaced another person's details on a shared office computer.

Messy contact data costs real time. People were being emailed twice, and nobody trusted the lead lists. The marketing manager had tried tidying the duplicates by hand, but they kept coming back.

What we found.

The sales system decides whether a form submission is a new person or an existing one by matching on the email address. The form in question did not ask for an email address on its first step, so the system fell back on matching by the visitor's web browser. On a shared computer, the next person was treated as the previous one.

We looked at the one form the team named. The company had other forms and connections, and those may behave differently, so we listed them as not examined.

The technical detail

The form had no email field on its first step, so HubSpot matched submissions by browser cookie, which can overwrite one contact with another on a shared browser. We added the email field to that step and set contacts to match on email address and companies on website address, then recorded the previous settings so the change can be reversed.

What we did.

How the work ranSteps in order: 1 Agree one form: The form, the matching rule and the test contacts; 2 Reproduce it: Made-up submissions show the duplicate; 3 Find the cause: Which setting or step creates it; 4 Make the smallest change: With the old setting written down; 5 Test six submissions: Counts recorded after each; 6 Review and hand over: You delete the test contacts and try one real submission. You decide at step 1 and step 6.1 Agree one formThe form, the matchingrule and the testcontacts2 Reproduce itMade-up submissionsshow the duplicate3 Find the causeWhich setting or stepcreates it4 Make the smallestchangeWith the old settingwritten down5 Test sixsubmissionsCounts recorded aftereach6 Review and handoverYou delete the testcontacts and try onereal submissionYou decide here How the work ranSteps in order: 1 Agree one form: The form, the matching rule and the test contacts; 2 Reproduce it: Made-up submissions show the duplicate; 3 Find the cause: Which setting or step creates it; 4 Make the smallest change: With the old setting written down; 5 Test six submissions: Counts recorded after each; 6 Review and hand over: You delete the test contacts and try one real submission. You decide at step 1 and step 6.1 Agree one formThe form, the matching rule and the testcontacts2 Reproduce itMade-up submissions show the duplicate3 Find the causeWhich setting or step creates it4 Make the smallest changeWith the old setting written down5 Test six submissionsCounts recorded after each6 Review and hand overYou delete the test contacts and try one realsubmissionYou decide here
The steps in order. A box with a coloured border is where the client decided.

How we checked it.

These had to pass before we asked for sign-off.

  • Submitting the same made-up email address twice through the form left exactly one contact, with both submissions in its history.
  • Two different made-up addresses at one made-up company left two contacts and one company.
  • Two different made-up people on one browser stayed two separate contacts, neither overwritten by the other.
  • The change notes list every setting changed with its old value, and no real contact was merged, deleted or messaged during testing.

What they have now.

The team received a short note naming the cause, the changed form setting with notes on how to reverse it, before-and-after contact and company counts for the six test submissions, and a list of the other forms in the account that we had not examined.

The marketing manager deleted the test contacts and checked one real submission in their own account before signing off.

What we did not do.

  • We changed one form only. Other forms and connections may behave differently, and we listed them.
  • We did not merge or delete the duplicates already in the system. Merged contacts cannot be unmerged, so that is a separate and careful job.
  • We gave no advice on consent or data protection.
  • Duplicates created by a sync with another system follow different rules and were outside this job.

The service behind this.

When the same person keeps appearing twice in your sales system, the cause is usually one form or one connection. Finding which is quicker than tidying duplicates by hand.

One-off job

Stop duplicate HubSpot leads

Synthetic submissions through one HubSpot form or API integration give the agreed counts: one contact for a repeat email, one company for two people at one domain, and no merging of different people.

$295. $295 after the agreed checks pass and you sign off. No payment before sign-off.

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