Dial-in means joining the audio portion of a webinar by phone instead of through your computer's microphone and speakers. You get a phone number and an access code, usually sent in the invite or reminder email.
Webinar Glossary
Dial-in
Attendees dial-in to a webinar or video conference when they connect to the event using a phone.
What is dial-in?
Dial-in is when attendees of a webinar or video conference connect to the event using a phone. Dial-in is used to overcome issues with audio and video. Traditional dial-in is possible with VolP technology. For webinars, SIP is used to facilitate the calls.
What is VolP?
VolP, or voice over internet protocol, is any call made over the internet rather than via traditional phone lines. VolP is also called broadband phone service. Only voice can be exchanged with VolP. It is a low-cost communication method.
What is SIP
SIP stands for Session Initiation Protocol. It is an internet protocol that is used to send messages, video, voice, data, and other media in VolP applications for free.
How does dial-in work, and what does it cost?
Most webinar platforms, including Livestorm, offer dial-in through a VoIP telephony partner, letting attendees join the audio portion of a webinar from a landline or mobile phone instead of a computer microphone. It’s typically used as a fallback when someone’s internet connection can’t support browser-based audio, or when they need to join from a car, a train, or an area with unreliable Wi-Fi.
Setting up dial-in usually involves three steps: generating a unique access code for the session, assigning local or toll-free numbers for the audience’s region, and sharing both in the calendar invite and reminder emails alongside the standard join link. Because international toll-free numbers are billed per minute by the telephony provider, most platforms cover a default set of countries and let organizers add more as needed.
One limitation worth flagging to attendees: dial-in participants can listen and speak, but they can’t see shared screens, slides, or chat — so hosts running dial-in-heavy sessions should narrate visuals out loud and read chat questions aloud before answering them.
Editorial & methodology — Written and reviewed by the Livestorm content team, based on first-party product experience and platform documentation. Last updated: July 2026.
Frequently Asked Questions
What does dial-in actually mean for a webinar?
Does dial-in cost the attendee anything?
It depends on the number type. Toll-free numbers are free for the caller since the organizer is billed instead, while local numbers may carry standard call charges depending on the attendee's phone plan.
Can dial-in attendees ask questions?
Yes, typically by pressing a key combination to raise their hand, after which the host can unmute them. This varies by platform.
Why would someone use dial-in instead of just joining online?
Usually a connectivity issue, like no Wi-Fi or a weak signal, or a situational one, like being in the car when video isn't practical but audio still is.
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