How many custom fields does Planner Premium support?
Ten per plan, in five types. Text, Number, Date, Yes/No and Choice. Custom fields are premium only, so a basic plan has none at all.
The number is rarely what bites, though, and it is worth being straight about that before spending a page on it.
Ten is usually enough
A single team tracking a handful of attributes rarely reaches the tenth field. The five types cover the ordinary cases:
- Text, for anything that does not fit the others
- Number, for counts and amounts
- Date, for a milestone or a deadline that is not the task dates
- Yes or No, for a flag
- Choice, for a fixed list of options you define on that plan
If the count is the only thing troubling you, this is not a real constraint on your work. Where it goes wrong is scope, not quantity.
Ten fields on a plan is not a data model
A custom field in Planner Premium belongs to the plan it was created on. That is invisible while one team looks at one plan, and it is the whole problem the moment anyone wants to count something across forty of them.
The field belongs to the plan, not the organisation
Each plan defines its own ten. Two managers who both want to track priority create two separate fields that happen to share a name, and a third who calls it "Urgency" creates a third. Project Online defined enterprise fields once, centrally, so the same field meant the same thing everywhere it appeared.
Nothing standardises what goes in them
A Choice field fixes the options on that one plan, and nothing keeps two plans in step. So High, P1 and Critical are all perfectly valid entries for the same idea in three different plans. Project Online had lookup tables specifically to stop that, because the whole reason for standardising terminology is being able to count it later.
Nothing is computed
The five types hold what somebody typed. There are no formulas, no Max, Min, Sum or Average rollup on a number field, and no graphical indicators driven from a threshold. Project Online had all four, which is how a red flag on a summary row got there without anyone deciding to put it there.
Which is why this question and the reporting question are the same question wearing a different hat. A report across the portfolio needs one field with agreed values, and per-plan fields do not produce one.
Ten fields and the five types are from Microsoft Support's premium capabilities article; formulas, lookup tables, rollups and graphical indicators are documented under Project Online on Microsoft Learn. Both checked 25 August 2026. Microsoft ships Planner monthly, so check the current position before you plan around it.
How Onplana handles it
Twelve field types rather than five, adding currency, rating, URL, email, phone, multi-line text and multi-select, with no cap on how many you create. Professional and above.
The part that matters more is scope. A field can be defined once for the whole organisation, so every project shares the same field and the same option list and a report across the portfolio has something real to count. It can also be scoped to a single project when the thing genuinely is local to that work, which is the case per-plan fields serve well and the only case they serve.
One concession, in the same breath: we have no formula fields and no graphical indicators either. Project Online had both. Health rollups, earned value and portfolio status are computed here, but they are built in rather than something you assemble from a formula on a field you invented. If that specific capability is load-bearing for your PMO, make every vendor demonstrate it rather than describe it.
Common questions
How many custom fields can a Microsoft Planner Premium plan have?
Ten. Microsoft Support states you can create up to ten new fields on a premium plan, and a Microsoft Q&A moderator separately gives ten custom fields per project when listing premium limits, both checked 25 August 2026. It is a per-plan allowance, so a second plan gets its own ten rather than sharing yours.
What types of custom field are available?
Five: Text, Number, Date, Yes/No, and Choice. Choice lets you define a fixed list of options for that field on that plan. Custom fields are a premium-only capability, so they are not available on basic Planner plans at all.
Is ten enough?
For most teams, comfortably. This is worth saying plainly because "only ten" is the weak version of the argument and anyone who has run a plan will see through it. A single team tracking a handful of attributes rarely reaches the tenth field, and if the count is the only thing troubling you then this is not a real constraint on your work.
So what actually goes wrong?
Scope, rather than quantity. A field belongs to a plan, so nothing makes your Priority field and another manager's Priority field the same field, and nothing keeps their allowed values in step. That is fine while one team is looking at one plan, and it stops being fine the moment somebody wants to count something across forty of them, because there is no single field there to count.
Can a Planner custom field use a formula or roll up?
Not that Microsoft documents. The support page describing custom fields lists the five types and says nothing about formulas, calculated values, lookup tables or rolling values up across plans. Project Online documented all of those under Enterprise Custom Fields, including Max, Min, Sum and Average rollups on number fields and graphical indicators with separate criteria for summary rows.
What happens to my Project Online enterprise custom fields when I migrate?
Different question, and not one to answer by inference from this page. What a product has and what a migration carries are separate claims, and conflating them is how comparison pages end up wrong. Export your field definitions and their lookup tables while Project Online is still live, whichever platform you land on.
What does Onplana do here?
Twelve field types rather than five, including currency, rating, URL, email, phone, multi-line text and multi-select, with no cap on how many you create. Available on Professional and above. The part that matters more is scope: a field can be defined once for the whole organisation, so every project shares the same field and the same option list, or scoped to a single project when it genuinely is local to that work.
Does Onplana have formula fields?
No, and you should hold that against us in the same breath as anything else on this page. We have no calculated custom fields and no graphical indicators driven from a threshold, both of which Project Online had. Health rollups, earned value and portfolio status are computed in Onplana, but they are built-in rather than something you assemble yourself out of a formula on a custom field. If a formula-driven field is load-bearing for your PMO, make every vendor demonstrate it.