Short answer: a trade show or webinar gives you a natural reason to write, provided you say where the contact comes from. Send the message within two or three days, quote the event and one precise point from the exchange, and keep the offer for later. If the person told you nothing, do not pretend otherwise.
What kind of contact do you have?
The right message depends on how you got the contact. Three cases come up.
| Case | What you can say | Precaution |
|---|---|---|
| Met in person (booth, round table, coffee) | "Great to talk about..." | Recall one precise point of the conversation |
| Registered for or attended your own webinar | "Thanks for joining..." | Say what you will do with their address, leave them the choice |
| Attendee of a third-party event, no exchange | "We were both at..." | Only write if there is a clear link to them |
LinkedIn states that the organizers and attendees of an event can view the complete attendee list from the event page (LinkedIn Help, accessed October 8, 2026). That list is not a free prospecting database: write only to people for whom you have a precise reason.
When should you write?
Within two or three days of the event. It is a field rule of thumb, not a measurement. After fifteen days the person has forgotten the conversation, and your message looks like ordinary prospecting.
Which message templates should you send?
Square brackets are for you to replace.
1. Met in person
Hi [First name], great to talk yesterday at [place or booth]. You mentioned [precise point]. I thought of [useful resource], shall I send it over?
2. Attended your webinar
Hi [First name], thanks for joining [webinar title]. Which part spoke to you most? I am preparing the next one and your view would help.
3. Registered but absent
Hi [First name], you could not join [title]: here is the recording. The part on [topic] is the most useful if you only have ten minutes.
4. Attendee of a third-party event
Hi [First name], we were both at [event]. Your question about [topic] made me think. How did you solve that at your company?
Template 4 only works if the person really asked that question, in public. Otherwise, do not invent it.
How do you handle the list?
Sort before you write. People you spoke with come first, with a message written for them. Registrants with no exchange get a shorter message, with the choice to stop being contacted. Leave out peers, suppliers and journalists, unless they are exactly your audience.
Sales Farmer imports a CSV list, or a list of LinkedIn addresses, for a manual campaign, on every plan. The sequence stops as soon as the person replies, and variables such as {{role}} or the first name take a fallback text when the data is missing. The contact base stays under your responsibility: see our guide to LinkedIn prospecting and GDPR.
Which mistakes should you avoid?
- Sending the same text to everyone, including people who never spoke to you.
- Writing too late. After fifteen days the conversation is cold.
- Signing someone up to a newsletter without asking. It is a different act from writing to them.
- Selling in the first message. The first message extends the exchange, it does not replace it.
- Saying "we talked" when it is not true.
FAQ
How long after a trade show should you write?
Within two or three days, while the memory is fresh. After two weeks, mention the event in half a sentence only.
Can you contact the attendees of a LinkedIn event?
Technically the list is visible to attendees. But writing to everyone makes no sense: pick the ones for whom you have a precise link with the event, and be ready to say where the contact came from.
Should you ask for agreement before adding someone to a newsletter?
Yes. Writing once to extend an exchange and signing someone up to a mailing list are two different things, with different rules.
What do you say when you did not speak to the person?
Say it simply: "we were at the same event", then lean on a verifiable fact about them. Avoid suggesting a meeting that did not happen.