If your work is genuinely schedule-driven — baselines, critical path, lead and lag dependencies — Microsoft’s Planner and Project Plan 3 at $30 per user per month is the closer fit. If most of your team updates tasks rather than builds schedules, Smartsheet Business at $19 is cheaper and lands faster. Plenty of PMOs end up running both.
September 30, 2026 is the date forcing this question
Project Online retires on September 30, 2026. Microsoft’s Planner FAQ lays out the sequence plainly: end of sale for Project Online-only SKUs for new customers on October 1, 2025, then full support for existing customers until the retirement date. After that, the guidance is to back up your data and finish the transition — not to wait and see.
Two details in that announcement deserve a second read.
First, it is Project Online specifically. Microsoft states the retirement does not affect Project desktop, Project Server Subscription Edition, or Planner. So if your real dependency is a handful of .mpp files and one scheduler who lives in the desktop client, your exposure is smaller than the vendor blog posts imply.
Second, there is no clean automatic path out. Microsoft says native migration tools exist for moving project data from Project Online into Planner, but environments with custom code and integrations will likely need a partner. For Project Online to Project Server Subscription Edition — the closest feature-for-feature landing spot — Microsoft states outright that it does not provide a migration tool and recommends working with an experienced partner.
That is precisely why PMOs are evaluating Smartsheet this year rather than simply re-platforming inside Microsoft. If you are rebuilding regardless, the cost of leaving starts to look a lot like the cost of staying.
One more piece of housekeeping: Project for the web has already been retired and folded into Planner for the web, and Project Plan 3 and Plan 5 were renamed Planner and Project Plan 3 and Plan 5 back in September 2024. So “Microsoft Project” in 2026 means one of three different products — Planner premium in the browser, the Project desktop app, or on-prem Project Server. Be specific about which one you are actually comparing.
One is a work grid, the other is a scheduling engine
Smartsheet began as a spreadsheet that grew project features. Microsoft Project began as a scheduling engine that grew a web front end. Both origins still show.
In Smartsheet the unit of work is a row. Dependencies, durations and predecessors are behaviours you switch on in sheet settings, not the underlying data model. That is why Smartsheet absorbs intake forms, risk registers, budget trackers and executive dashboards so readily — they are all just sheets. It is also why a scheduler who thinks in constraint types and resource calendars will feel like something is missing.
In Planner and Project, the schedule is the model. Tasks carry durations, dependencies with lead and lag, baselines, and a critical path the engine calculates.
Neither approach is better in the abstract. They fail differently. Smartsheet’s failure mode is sprawl: four hundred sheets, no naming convention, three competing versions of the truth. Project’s failure mode is an immaculately maintained schedule that nobody outside the PMO ever opens.
What 25 seats actually cost
Published US list prices, checked July 2026.
Smartsheet sells by Member. Pro is $9 per member per month billed yearly ($12 month-to-month) and caps at 10 members — so a 25-person PMO cannot buy Pro at all. Business is $19 billed yearly ($24 month-to-month), minimum three members. Twenty-five Business members works out to $475 a month, $5,700 a year, per smartsheet.com/pricing.
What makes that number defensible is who does not need a seat. Contributors — people who view, comment, attach files, respond to update requests and submit forms — are free and unlimited on every paid plan. Free external Guests start at Business. A 25-person PMO serving 300 stakeholders licenses 25 seats, not 325.
Microsoft sells by capability tier instead. Planner comes with an eligible Microsoft 365 subscription at no extra license. Planner Plan 1 is $10 per user per month paid yearly and adds Timeline (Gantt), People and Goals views, task dependencies, backlogs and sprints, milestones and custom fields. Planner and Project Plan 3 is $30 and is where baselines, critical path, advanced dependencies with lead and lag, portfolio creation and the Project desktop app live.
So the 25-person comparison hinges entirely on how many of those people build schedules:
- 25 on Plan 3: $750 a month, $9,000 a year
- 5 on Plan 3 plus 20 on Plan 1: $350 a month, $4,200 a year
- 5 on Plan 3 plus 20 on Planner in Microsoft 365: $150 a month, $1,800 a year
That last row is the one most comparisons skip. Microsoft’s FAQ confirms Planner-in-Microsoft-365 users can edit premium plans created by a licensed user — assigning tasks, changing start and finish dates, adding attachments. They simply cannot reach the Timeline, People and Goals views without Plan 1. If you already pay for Microsoft 365 and only a few people own the schedule, Microsoft undercuts Smartsheet badly.
Where Smartsheet’s $19 stops being $19 is add-ons. Data Shuttle starts at $100 a month, Dynamic View at $125 a month, both on top of seats. Resource Management is an add-on on Business and above — not included at any tier, and it is exactly the capability Project Online refugees assume they are buying. Control Center, Connectors, DataMesh and Bridge follow the same pattern. Enterprise and Advanced Work Management are quote-only.
Price the add-ons during evaluation, not at renewal. If you are still deciding whether either tool justifies a per-seat line, our rundown of free project management tools covers what you can get for nothing first.
Scheduling depth: what Smartsheet does, and where it stops
Smartsheet has a genuine critical path, and it works the way you would expect. Enable Dependencies in sheet settings, give every task a start date plus an end date or duration, assign predecessors, then click Show Critical Path in the upper right — the driving sequence highlights red in Gantt view. It is available on Pro, Business and Enterprise. Only sheet Owners and Admins can turn dependencies on; anyone with Editor rights can show or hide the path afterwards. Summary path and driving path tools exist for working out why a date moved. Our Smartsheet Gantt chart setup guide walks through the sheet settings in order.
Baselines are Business and up — not on Pro. Timeline view and workload tracking are also Business and up. Portfolios and Scenario Planning are Enterprise. Resource Management, as noted, is priced separately.
Now the uncomfortable part. Smartsheet’s scheduling is fundamentally per-sheet. Cross-project resource contention, enterprise resource pools and portfolio capacity planning sit in add-on and Enterprise territory, not in a $19 seat. Project’s engine carries decades of work on constraint types, calendars and levelling that a row-and-column model does not try to replicate. If your schedules are litigated — construction claims, regulated programme delivery, anything where the baseline is a contractual artefact — that gap decides the whole thing.
On AI, Smartsheet’s Smart Assist went generally available on June 3, 2026, across Pro, Business, Enterprise and Advanced Work Management. It summarises sheets, drafts stakeholder updates, adds and edits rows and columns, and builds dashboards from a prompt. Smart Columns and the AI dashboard builder are on every paid plan; the ChatGPT connection and MCP-based integrations start at Business. The agent-based capabilities are a separate and less settled story — we track their status in our piece on Smartsheet Smart Agents. Microsoft’s comparable depth means adding Microsoft 365 Copilot at $30 per user per month on top of your Planner license, which materially changes the arithmetic above.
Leaving Project Online: what actually breaks
Smartsheet’s own documentation is refreshingly candid here, which makes planning easier. There are two routes off Project Online and neither is a single button.
The file route: Smartsheet imports Microsoft Project files in .mpp, .mpx, .mspdi or .xml format, capped at 50 MB and 20,000 rows, 400 columns or 500,000 cells per import. Project features Smartsheet does not support — constraints among them — can push rows out of order on .mpp import. Smartsheet’s documented workaround is to save the file as .xml and import that copy instead.
The Project Web App route, for teams without the desktop client, goes through Excel. Per Smartsheet’s migration article:
- In Project Web App, open Project Center, select Projects on the ribbon, then Export to Excel for the portfolio summary.
- Open each project, go to Tasks or Schedule, and use Export to Excel again for task-level detail.
- Clean the workbook — delete anything above the header row, and drag the data you want into the left-most tab, because Smartsheet only imports the first tab.
- In Smartsheet, select + Create, then Import, then Microsoft Excel, name the sheet and choose a Primary column.
What you lose, according to Smartsheet’s own limitations table: hierarchy (every row arrives top-level and you re-indent by hand), functional dependencies (Project Online predecessors come across as plain text, so you retype them into the Predecessor column), column types (dates frequently land as Text/Number), plus merged cells, borders and validation dropdowns. Formulas do not survive either.
For a four-project pilot that is an afternoon. For 200 active projects with custom fields and downstream integrations it is a staffed workstream, and it should be budgeted as one. If you will be shuttling data between Smartsheet and other systems on a schedule afterwards, that is what the $100-a-month add-on is for — our Data Shuttle setup guide covers the configuration.
When not to switch
Three cases where staying inside Microsoft is the better decision.
Your baselines are contractual. Smartsheet’s baselines are perfectly usable for tracking variance, but the surrounding machinery — constraint handling, levelling, enterprise resource pools — is not equivalent, and some of it is not available at any Smartsheet price without add-ons.
Only a few people build schedules. Five Plan 3 licenses alongside twenty users on Planner in Microsoft 365 costs roughly $150 a month for 25 people, against $475 for Smartsheet Business. Your team is already in Teams. That is a hard argument to beat on cost alone.
You have deep Project Online integrations. Microsoft confirms the Project Online OData endpoints and the ProjectData API remain supported through the Planner transition, so if the September date is your only real pressure, Project Server Subscription Edition keeps your integration patterns far closer to intact than a jump to Smartsheet. Just remember there is no Microsoft-supplied migration tool for that path either — budget for a partner.
And if the actual complaint is that Project is too heavy rather than too expensive, Smartsheet may not be the lightest thing worth trialling. Our ClickUp versus Microsoft Project comparison covers the other end of that spectrum.
Side by side
| Capability | Smartsheet | Microsoft Planner and Project |
|---|---|---|
| Entry paid tier | Pro $9/member/month yearly, max 10 members | Planner Plan 1 $10/user/month yearly |
| Tier most PMOs need | Business $19/member/month yearly | Planner and Project Plan 3 $30/user/month yearly |
| Free collaborators | Unlimited Contributors on all plans; free Guests from Business | Planner in Microsoft 365 users can edit premium plans |
| Gantt / Timeline | Gantt on Pro; Timeline view from Business | Timeline (Gantt) from Plan 1 |
| Baselines | Business and above | Plan 3 |
| Critical path | Pro, Business, Enterprise (needs Dependencies enabled) | Plan 3 |
| Resource management | Paid add-on, Business and above | Included from Plan 3 |
| Portfolios | Enterprise | View on Plan 1, create on Plan 3 |
| Built-in AI | Smart Assist on all paid plans since June 3, 2026 | Microsoft 365 Copilot add-on, $30/user/month |
| 2026 status | Stable; Smart Assist GA | Project Online retires September 30, 2026 |
One note on Planner and Project Plan 5: it no longer appears on Microsoft’s public Planner plan comparison page as of this check. If you hold Plan 5 licenses, confirm current status directly with your Microsoft licensing contact rather than relying on third-party pricing pages.
Common questions
Is Smartsheet a direct replacement for Microsoft Project?
Not a like-for-like one. Smartsheet covers Gantt, dependencies, critical path and baselines, but resource management is a paid add-on and portfolio features sit at Enterprise. For contractual scheduling with enterprise resource pools, Project Server Subscription Edition is the closer replacement for Project Online.
What happens to my data when Project Online retires?
Microsoft says existing customers keep full support until September 30, 2026, with projects, integrations and member access working normally until then. After the retirement date you lose access to projects and associated data in the service, so back everything up and finish your transition beforehand.
Does Smartsheet actually calculate a critical path?
Yes. Enable Dependencies in sheet settings, give each task a start date plus an end date or duration, assign predecessors, then select Show Critical Path in Gantt view. Tasks on the path highlight red. Available on Pro, Business and Enterprise; only Owners and Admins can enable dependencies.
Which is cheaper for a 25-person PMO?
Usually Microsoft, if you already hold Microsoft 365. Five Plan 3 seats plus twenty Planner-in-Microsoft-365 users runs about $150 a month. Smartsheet Business for 25 members is $475 a month before add-ons like Data Shuttle at $100 or Dynamic View at $125.
Can I import .mpp files straight into Smartsheet?
Yes, in .mpp, .mpx, .mspdi or .xml format, up to 50 MB and 20,000 rows. Unsupported Project features such as constraints can reorder rows on .mpp import; Smartsheet recommends saving as .xml and importing that instead. Expect to rebuild hierarchy and predecessors manually.
