Yes. Slido has a permanently free plan called Basic, it does not expire, and for a session that is mostly questions it is more generous than people expect: the Q&A is unlimited. The limits that bite are polls, participants and moderation, and they bite in predictable places. Here is what Basic includes as of September 2026, where it stops, and what to do when it does.
If the wall you are about to hit is moderation, it is free at askone.org — along with every other feature, and with an AI first pass for the sessions you run alone.
AskOne is made by The Product Compass. Slido belongs to Cisco, every other tool here belongs to someone else, and their free-tier figures come from each vendor's own pricing and help pages, read in September 2026.
Last updated: September 21, 2026. Free plans move quietly; every figure below carries the date it was checked.
What the Basic Plan Includes
Unlimited audience Q&A. Questions and upvotes are not metered. For most sessions this is the feature, and it is free.
Three polls per slido. Slido's community answer confirms three, and notes that some regions get five.
One quiz per event — but up to thirty questions inside that one quiz, which is more room than "one quiz" suggests.
Up to 100 participants per event. Per event, not per poll.
No card, no clock. Basic does not expire and does not ask for payment details.
The shape of it: Slido gives away the questions and meters everything around them. If you are running a Q&A after a talk, you may never touch a paid feature. If your session is built out of polls, or needs someone to approve questions first, you will meet the wall while you are still preparing it.
Where It Stops
The fourth poll
The limit people actually meet, usually the evening before a workshop. Three polls and one quiz per event is a small budget for anything structured around interaction rather than questions.
The 101st participant
The cap is per event, so a webinar that grows past a hundred people does not degrade — it stops admitting them. If your worst case is 150, the free plan is not a plan.
Moderation
Holding a question until someone approves it is a paid feature, and so are the moderators who do it — both sit behind the upgrade on Slido's own plan comparison. This is the wall that matters most for all-hands meetings: on Basic, an anonymous question is on the screen behind whoever is speaking the moment it is typed. For a conference Q&A that is usually fine. For an internal town hall it is the reason the free plan is not a plan. And there is a second half to it that no paid tier solves either: somebody has to sit and read the queue while the session runs.
What Slido Charges When You Outgrow It
Third-party pricing trackers put the cheapest paid tier, Engage, at around $17.50 a month billed annually, with the higher tiers quoted rather than listed. Slido does not publish every number in a place you can read without a sales conversation, so treat that as an order of magnitude and check the pricing page for today's version. The question that matters more than the headline rate is whether you are buying one host or forty.
What To Do When You Hit a Wall
Split the session. Slido's own community suggests creating an event per presentation, which resets the poll budget. It is free, and it means juggling several join codes in one room. It does nothing for moderation.
Pay. If the company already has Webex or Teams and somebody else signs the invoice, this is the path of least resistance.
Use a tool that does not meter features. Which is the next section, and the rest of the shortlist is on the alternatives page.
One warning before you switch on price alone: the free plans in this category fail in different places, and a monthly meter is worse than a per-event one for anybody who runs sessions regularly. Mentimeter, the most common swap, allows 50 participants per month rather than per session — the detail is on the Mentimeter free-plan page, and the two free plans are compared directly on Slido vs Mentimeter.
The Free Tier Without the Moderation Wall
askone.org moves the meter. Every feature is in the free tier — live Q&A, polls, word clouds, rating scales, quizzes, the projector view, moderation, the AI first pass and the moderators who do it — and only capacity is paid. The audience joins with a link or a QR code and no account, questions are ranked by the room, and when the room closes the host gets the Q&A and the survey totals and can export them as CSV.
The meter is per room, and nothing counts down. This is the part worth reading twice, because it is where the free tiers in this category differ most. Most of them meter a calendar month: the account gets a pool of participants, every session draws from it, and when the pool is empty the next audience is refused until the month turns over. AskOne has no such counter. The cap is per room — a room admits up to 100 people, and you can open a room every day of the month without any of them counting against the next one. There is no monthly total, nothing resets, and nothing runs out.
And the first read does not have to be yours. A room is set to one of three things and you can change it mid-session: no moderation, hold every question for a person, or let the AI take the first pass. On that third setting each question is classified before anyone sees it, in about a third of a second — inside the wait the person asking already has — and it is included on every plan, within fair use.
It judges civility, never the subject. What it rejects is abuse, harassment, spam and keyboard-mashing. A question that has nothing to do with your session is not on that list, on purpose: in a room ranked by votes an irrelevant question sinks by itself, while a wrongly rejected one is gone and the person who asked it is told it was not accepted. Being wrong is expensive in one direction only, so what is on topic stays the host's call.
When it is not sure, a person decides. Below the confidence line — and on a timeout, or when the model is unreachable — the question waits in the moderation queue instead of being guessed at. The failure direction is always towards a human, never towards the wall.
Nothing is deleted and you can overrule it. Whatever the AI held back sits in its own list for the host to open and restore.
What leaves the room. In an AI room the question text and the room's name and description go to the model. No participant name, cookie or IP goes with them.
Measured on the release that shipped it: a hundred questions through the live classifier — none of the 55 civil ones rejected, 24 of the 25 abusive or spam ones caught outright and the 25th held for a person, so none of them reached the room. Median 315 ms against a two-and-a-half-second budget. It is re-run on every release, because a model can move underneath wording that did not.
You can open a real room right now, without signing up for anything. AskOne keeps one open to the public — askone.org/r/WQYJ7G. Vote a question up the list, answer the live survey, ask something of your own. It is a room on the running product rather than a video or a guided tour, and it resets itself every few hours, so nothing anyone leaves in it stays.
It is also where the AI first pass stops being a claim. A civil question typed into that room on 21 September 2026 was screened and on the wall immediately — inside the wait the person asking already has, which is the entire argument for letting a machine take the first read.
Free is one open room and up to 100 participants — no credit card, no trial clock. Premium raises that to ten open rooms and 1,000 participants per room, at $20 a month or $10 a month billed annually. Every feature on this page is on both plans, moderation and the AI pass included; what the paid plan buys is capacity, and your own logo in place of the small “Create your own room — free” line a free room shows its audience.
What is not there yet: single sign-on, a Teams or Zoom app, and PowerPoint integration. If your organisation buys software through a security review, that last one is the gap to know about.
Questions People Ask
Is Slido free forever, or just a trial?
Basic is a permanently free plan, not a trial. There is a separate trial of the paid features, which is why some accounts appear to lose functionality after a month — that is the trial ending, not the free plan changing.
How many polls can I run on Slido's free plan?
Three per event — Slido calls each event a slido — plus one quiz. Slido's community answer notes that some regions get five. Creating a separate event per presentation resets the budget.
How many people can join a free slido?
Up to 100 per event.
Does the free plan include Q&A moderation?
No. Moderation, and the moderators who do it, are on the paid plans. If your session depends on approving questions before the room sees them, budget for the upgrade — or use askone.org, where it is free and where the AI takes the first pass if you are running the session alone.
What is the best free alternative if the limits do not fit?
askone.org for a Q&A session, because nothing is metered except room size. The full comparison, including the tools built for classrooms and quizzes, is on the alternatives page.
Start free at askone.org: one open room, 100 participants, every feature including moderation, no credit card.