Open your sheet, choose Forms > Create form, then click the field whose answer should drive the rest. In Field Settings on the right, open the Logic tab and select Add Logic. Define a When condition, pick the Then targets, select Add, and save. Conditional logic needs a Business or Enterprise plan.
That last sentence is the part most tutorials bury. Smartsheet’s own help article for conditional logic in forms lists Business and Enterprise as the supported plans, with Owner or Admin permissions on the sheet. The public pricing comparison agrees: Conditional form logic is marked as not included on Pro, and included on Business. So if you are on a Pro subscription and the Logic tab looks inert, nothing is broken. You are looking at a plan boundary.
What conditional logic is actually solving
A flat intake form is a negotiation with your submitters. Every irrelevant question is a chance for someone to guess, skip, or abandon. Logic turns one form into several: the person requesting new hardware sees hardware questions, the person reporting a login problem sees support questions, and neither of them scrolls past twenty fields that do not apply.
The mechanism is deliberately narrow. A rule has one source field, a condition, and a set of targets. Targets are hidden until at least one condition that points at them is met. There is no branching to different pages, no calculation, no cross-field arithmetic. If you need any of that, you are past what forms do and into workflow territory.
Fix your columns before you open the Logic tab
Logic reads whatever the column gives it, so a sloppy column type produces a sloppy rule. Free-text fields make terrible sources — you would have to anticipate every spelling a human might type. Smartsheet’s documentation makes this point directly and suggests standardising submissions with dropdown lists that mimic numeric ranges: instead of a text box for budget, build a dropdown with options like Over $10,000, then key your rules off those values.
Here is what each column type gives you inside the form builder, drawn from the documented Display As and Validation tables in Smartsheet’s create-and-edit-a-form article.
| Column type | Display As options in the form builder | Field validation available |
|---|---|---|
| Text/Number | Single-line text box, multi-line text box | Numbers, percents, email addresses, phone numbers |
| Dropdown (Single-select) | Dropdown, vertical radio buttons, horizontal radio buttons | Not available; use Restrict to list values only |
| Dropdown (Multi-select) | Dropdown, vertical checkboxes, horizontal checkboxes | Not available; use Restrict to list values only |
| Checkbox | Title above, title to the right | Not available |
| Symbols | Dropdown, vertical radio buttons, horizontal radio buttons | Not available |
| Contact List | Not listed among the documented Display As options | Email addresses; Restrict to list values only |
| System columns | Cannot be added to a form at all | Not applicable |
Smartsheet says the operator in a condition varies by field type, but does not publish a per-type operator list. Build one throwaway rule against each column type you plan to use as a source and see what the blue operator dropdown offers before you design the whole form around an assumption. If you are still setting up your first sheet, the column decisions in our Smartsheet setup guide for beginners are worth settling first — changing a column type later has consequences, covered below.
Building the form
- Open or create the sheet that will store responses. Form fields map to that sheet’s columns, and every submission lands as a new row.
- Select Forms > Create form from the top menu bar. The form title defaults to the sheet name; overwrite it.
- Add fields from the Fields panel, or hover an existing field and select the + sign to create a new one. Adding a field this way also creates the matching column in the sheet.
- Drop in the non-question elements you want — Heading/Description, Divider, Attachment. You get one attachment field per form, capped at 30 MB per file and 10 files per submission, and uploads arrive as row attachments.
- Order the fields so your source questions come before anything they reveal. Logic does not reorder the form for you.
- Adjust form-level options in the Settings tab, then select Save at the top right.
Adding the first When/Then rule
- Select the source field — the one whose answer decides what appears next.
- In Field Settings on the right, open the Logic tab and select Add Logic.
- Complete the condition, which always begins with When: pick the operator and the source values that should trigger the reveal.
- Complete the action, which begins with Then: select every field and element you want shown. One rule can target many things at once.
- Select Add at the bottom right of the rule.
- Need a second rule on the same source field? Select +Add rule.
- Save, then select Open Form in the top-right corner of the Form Builder and click through it as a submitter would.
Back in the builder, source fields carry one logic icon and targets carry another. Hovering a target’s icon lists every condition currently pointing at it, which is the fastest way to audit a form someone else built.
Operators beat rule count
Three rules on one source field is usually two rules too many. If several dropdown answers should reveal the same block, use is any of in a single condition. If a field should appear in most cases except one, invert it with is not rather than enumerating every value that qualifies. This is not just tidiness — Smartsheet caps the combined size and number of rules on a single source field, and when you cross it the builder refuses to save with Sorry, there was a problem saving this logic. Logic statement is too large. Try reducing the conditions for the affected fields. The limit depends on both how many rules you built and how many fields each one selects, so there is no round number to design against. Tighter operators keep you well under it.
Nested reveals
A target field can also be a source field, which is how you build a chain: the answer to Question 1 reveals Question 2, and the answer to Question 2 reveals Question 3. The cascade collapses correctly — if Question 1 changes so that Question 2 disappears, Question 3 disappears with it.
Two rules apply everywhere in the tree. Targets are hidden by default and appear only when a condition is satisfied. And when several rules point at the same target, it appears the moment any one of them is met, not all of them. There is no AND across separate rules.
Depth is where nested forms go wrong. Three levels is comfortable. Five levels means a submitter can select one wrong dropdown value at the top and silently receive an entirely different form, with no way to tell they went down the wrong branch. Test every branch end to end before you share the link.
Revealing headings, dividers, and attachments
Fields are not the only valid targets. Headings, dividers, and the attachment field can all sit in a Then clause, and using them properly is what makes a conditional form read like a designed document instead of a set of questions that pop in and out.
Reveal the heading and its divider alongside the questions they introduce. A section header for Equipment Details hanging above nothing because its questions are hidden looks like a bug to a submitter. Gate the attachment field the same way — ask for a file only on the branches where a file makes sense, rather than leaving a permanent upload box that most people ignore.
The behaviours that catch people out
A hidden target submits nothing
Target fields only write to the sheet if they were visible when the form was submitted. This is the single most consequential documented behaviour, and it bites in a specific way: a submitter answers a question, changes their mind about the source field, the target collapses, and the answer they gave never reaches the sheet. Downstream formulas and reports see an empty cell, not a changed one. Design your sheet so blanks in conditional columns are expected rather than alarming.
Required only counts while visible
The Required flag on a target applies only when that target appears at submission time. That is the intended behaviour and it is genuinely useful — it is how you make a field mandatory on one branch and irrelevant on another. Just do not read a Required flag in the builder as a guarantee that the column will always be populated.
The Hidden toggle wins
If a field is switched on with the Hidden toggle in Field Settings, that overrides any logic rules attached to it. The field will not appear no matter which conditions fire. Every so often someone spends an afternoon debugging a rule that was never going to run because the field was hidden months earlier for an unrelated reason.
Hidden has a legitimate partner, though. Pair it with Default Value to write a value on every submission without showing the question: hide the Status field, set its default to Open, and every row arrives with a status. If a hidden field has no default value, remove it from the form instead of leaving it there.
Editing column values can affect existing rules
Smartsheet states that changing the Column Type or the Values of a field used in conditional logic may affect the rules built on it. Rename a dropdown option from Urgent to P1 and any rule keyed to Urgent is now pointing at a value nobody can select. The form still saves and still loads. It just stops revealing anything. Separately, removing a field from the form removes the logic attached to it — the sheet column stays put, since columns can only be deleted from the sheet itself.
Treat any dropdown-value edit on a form-connected column as a change that requires re-testing the form. Nothing warns you.
Logic depends on the sheet Owner’s licence
From Smartsheet’s forms FAQ: if you hold Owner permissions on a sheet with a form and you stop being a paid user, the conditional logic stops working. Worse, if no one in the organisation holds Owner permissions on that sheet, the form becomes completely inaccessible. The documented preventive step is to share the sheet to a colleague and transfer ownership before anyone leaves. Departure season is a bad time to discover which of your intake forms had a single point of failure.
When a form is the wrong tool
Forms create rows. They do not edit them. If your process needs the submitter to come back and change an answer, an update request workflow or Dynamic View is the documented path, not a second form submission that creates a duplicate row.
Forms also do not calculate. If you find yourself building a dropdown of budget bands so logic can approximate a numeric comparison, accept that as a workaround rather than a design, and put the real calculation in the sheet. Note that Smartsheet documents cases where formulas do not autofill onto new form rows — for example when the two rows near the new entry lack the formula, or the preceding row is indented in a hierarchy. If your calculated columns keep coming up blank, our guide to fixing Smartsheet formulas that are not working covers the usual causes; column formulas are the sturdier answer for form-fed sheets.
Two integration points are worth planning for while you build. New rows created by forms can trigger automated workflows — approvals, assignments, notifications — and if those workflows misfire, the diagnostic order in our piece on Smartsheet automations that are not triggering applies to form-triggered rules too. And if you need to restrict who reaches the form at all, Smartsheet documents embedding it in a web content widget on a dashboard and sharing the dashboard instead of the raw link, which pairs well with the reporting patterns in our Smartsheet dashboards guide.
Frequently asked questions
Can I use conditional logic on the Pro plan?
No. Smartsheet’s help article for conditional logic lists Business and Enterprise as the supported plans, and the public pricing comparison marks Conditional form logic as unavailable on Pro. Pro subscribers can still build and share forms, add validation, hide fields, and set default values — just not When/Then rules.
Does a hidden field still save its default value?
Yes. Smartsheet documents pairing the Hidden toggle with Default Value precisely for this: set Status to hidden with a default of Open, and every submission writes Open to the sheet without showing the question. If you do not need a stored value, remove the field from the form instead.
Can one answer reveal several fields at once?
Yes. A single Then clause can list several target fields and elements, so one answer can reveal a heading, three questions, and a divider together. Where more than one rule points at the same target, Smartsheet shows it as soon as any one of those rules is satisfied.
What happens to my rules if I delete a form field?
Removing a field from the form also removes the logic attached to it, per Smartsheet’s documentation. The underlying sheet column survives — deleting a column has to be done in the sheet itself. Assume you will rebuild the rule by hand after adding the field back to the form.
Can conditional logic make a field required only sometimes?
Effectively, yes. Smartsheet’s documented behaviour is that target fields are required only when they appear on the form at submission. Mark the target Required, gate it behind a rule, and it blocks submission when visible and is ignored entirely when the condition is not met.
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