When a Salesforce lead is converted, its related records are moved, not copied: all open and closed activities attach to the resulting account, contact, and opportunity; notes and attachments transfer to the new account and contact; and campaign memberships carry over to the new contact. The lead itself becomes a read-only record that still feeds lead reports. Custom lead fields only survive the trip if an admin has mapped them to account, contact, or opportunity fields in advance — anything unmapped is stranded on a record most users can no longer see. This guide walks through exactly what moves, what does not, who owns what afterward, and the surprises teams hit in their first week of converting at volume — the same conversion design questions Vantage Point answers in Salesforce implementation engagements.
Few standard Salesforce behaviors generate as many confused admin tickets as lead conversion. A rep converts a lead, then someone asks where the logged calls went, why an opportunity is missing a value that was "definitely on the lead," or why a task closed itself. The answers are deterministic — conversion follows exact rules — but the rules are spread across several help pages and almost nobody reads them until something looks wrong.
Here is the complete map.
Converting a lead produces up to three records: an account, a contact, and optionally an opportunity. You can convert against an existing account (and existing contact, with matching) instead of creating new ones. Everything the lead accumulated then has to find a home among those records — which is where the specific rules begin.
Activities follow the broadest path:
One behavior genuinely surprises people: these are shared references, not independent copies. If you delete one of these activities from any of the resulting records, Salesforce removes it from the others too. The recovery path is the recycle bin — restoring the activity there returns it to all the resulting records. So treat post-conversion cleanup of "duplicate-looking" activities with suspicion; they are usually the same activity seen from three records.
Conversion also touches system fields: Salesforce updates Last Modified Date and Last Modified By on the converted lead and on all related open and closed activities, because the Name and Related To values on those activities are rewritten to point at the new records. If you run reports or integrations keyed on activity modification timestamps, expect a wave of touches after a bulk conversion.
Standard lead fields land on their obvious counterparts. Custom lead fields do nothing by default — an admin must first map each one to a custom account, contact, or opportunity field under lead conversion field mapping settings. Unmapped custom values remain on the converted lead, which most users cannot see.
Two practical consequences:
Conversion lets you assign new owners for the created records, and activity ownership follows its own rules:
The net effect: only the open workload reliably follows the new owner. If your team converts leads on behalf of others, verify open-task ownership afterward — the split rules above are a frequent source of "my task disappeared" reports.
Sort of. The converted lead becomes read-only and is hidden from normal views unless a user has the View and Edit Converted Leads permission. It is not deleted: it continues to contribute to lead reports, which is what keeps conversion-rate and lead-source reporting honest. What you cannot do is treat it as a working record — edits to the account or contact do not flow back to the lead, and the lead is no longer the place to look for current truth. After conversion, the account/contact/opportunity are the system of record.
Vantage Point designs lead lifecycles — conversion mapping, record ownership rules, duplicate handling, and the automation around them — as part of Salesforce implementation and advisory engagements. If your org has years of unmapped custom fields or conversion behavior nobody can explain, our managed services team can audit and untangle it. Senior consultants only — no junior handoffs; the experts you meet are the experts who deliver.
If converting a lead feels risky, the design — not the button — is the problem. Contact Vantage Point for a working session on your lead lifecycle, or explore our Salesforce services.
They move — the same activity records are re-pointed to the new account, contact, and opportunity, not duplicated. That is why deleting a converted activity from one record removes it from all of them, and why restoring it from the recycle bin brings it back everywhere. Sales Engagement cadence activities are the exception and do not transfer.
No. Notes and attachments from the lead transfer to the resulting account and contact only. If your process needs a document on the opportunity — a signed scope document, for example — move or reference it there explicitly as part of your conversion checklist.
Campaign memberships move from the lead to the new contact, so marketing touch history and campaign influence reporting continue uninterrupted. This is automatic and requires no field mapping.
Because custom lead fields only carry over when an administrator has mapped them to a custom account, contact, or opportunity field in the lead conversion mapping settings. Unmapped values stay on the converted lead, which is read-only and hidden from most users. The fix is to create the target field, add the mapping, and then recover values from the converted leads if needed.
Open tasks assigned to the user performing the conversion move to the new record owner; open tasks assigned to other users keep their owners. Events owned by the converting user move to the new owner regardless of status. After a bulk or delegated conversion, spot-check open-task ownership — it is the most common loose end.
No. It becomes read-only and hidden unless you have the View and Edit Converted Leads permission, but it still exists and still contributes data to lead reports. You cannot edit it, and later changes on the account or contact do not sync back to it.
Vantage Point is a boutique CRM consulting firm helping businesses transform with Salesforce, HubSpot, and AI. Learn more at vantagepoint.io.