How to Flatten a PDF in Bluebeam Revu (and Unflatten It)
Flatten markups in Bluebeam Revu 21 with Document > Flatten Markups or Ctrl+Shift+M, choose the right options, batch a whole set, and unflatten when needed.
Published
To flatten a PDF in Bluebeam Revu 21, go to Document > Flatten Markups (Ctrl+Shift+M), choose which markup types to flatten, decide whether to tick Allow Markup Recovery (Unflatten), and click Flatten. For one or two markups, right-click them and choose Flatten. Then save the file. Flattening merges the markups into the page so they can no longer be moved or edited.
Bluebeam steps here come from its Revu 21 manual page Flatten markups, its article Locking vs. flattening markups and its troubleshooting article Editing a flattened PDF prevents markups from being unflattened, all checked November 12, 2026. The two articles apply to Revu 21 and Revu 20.
What does flattening a PDF in Bluebeam do?
Flattening in Bluebeam Revu merges markups into the content layer of the PDF. A flattened markup is no longer an object you can select: it drops out of the Markups list, it can't be edited, and Bluebeam notes it then displays in viewers that only show PDF content and its text becomes searchable.
People flatten before a set leaves the office (a submittal, an IFC set, a page going to a sub) so the reviewer sees exactly what you drew and nobody moves a cloud by accident.
How do you flatten selected markups in Revu 21?
Use this when only some markups, such as approved comments, should become permanent.
- Select one or more markups on the page or in the Markups list.
- Right-click one of them and choose Flatten.
The right-click route uses the default settings, which keep unflatten available. To set the options yourself:
- Select the markups.
- Go to Document > Flatten Markups.
- Under Flatten, choose Currently Selected Markups.
- Set the other options (table below) and click Flatten.
- Save the file.
Bluebeam notes that you can flatten a single markup but can't unflatten one on its own. Unflatten brings back every flattened markup on the page.
How do you flatten all markups in a PDF?
- Open the PDF in Revu.
- Go to Document > Flatten Markups, or press
Ctrl+Shift+M. - Untick any markup types you want to keep live in the type list. Everything ticked gets flattened.
- Under Flatten, choose All Markups.
- Decide on Allow Markup Recovery (Unflatten): ticked if you might need the markups back, unticked if the file is leaving the office.
- Set the Pages dropdown for the file (All Pages, Current, Selected or Custom).
- Click Flatten.
- Click Save As to save a new file, or Save to overwrite the current one.
Bluebeam's keyboard shortcuts page (Revu 21 and Revu 20) lists Ctrl+Shift+M for Flatten and Ctrl+Shift+U for Unflatten. Shortcuts can be changed per install, so if they don't work, check Revu > Keyboard Shortcuts.
The Flatten Markups options that matter
| Option | What it does | When to use it |
|---|---|---|
| Markup type list | Only the ticked types are flattened | Keep measurements or hyperlinks live while flattening comments |
| All Markups | Flattens every markup of the ticked types, filtered or not | Final issue of the whole file |
| Exclude Filtered Markups | Skips markups hidden by a filter in the Markups list | Filter out internal notes first, then flatten the rest |
| Currently Selected Markups | Flattens only what you selected before opening the dialog | Approving a few comments; unavailable if nothing is selected |
| Allow Markup Recovery (Unflatten) | Keeps the data needed to unflatten later | On for your own working copies, off for files you send |
| Flatten to Layer | Puts the flattened markups on a named PDF layer | When the receiver should be able to switch your markups off as a layer |
| Overlay Text | Prints the layer name beside flattened markups | Labeling who marked up what on a combined set |
| Show Properties in Popup | Keeps chosen markup properties in a popup | When the subject, author or status must survive; otherwise properties are lost |
| Pages | All Pages, Current, Selected or Custom (such as 1-3, 5, 9) | Flatten only the sheets being issued |
Bluebeam's manual is direct about the recovery box: flattening is irreversible if the PDF is flattened without Allow Markup Recovery (Unflatten) selected.
How do you flatten markups on a whole drawing set?
The same dialog flattens many files at once from Batch > Flatten Markups.
- Go to Batch > Flatten Markups.
- Use the Add menu to add Files, Open Files, Open Set, Folder, or Folder and Subfolders.
- Drag the files into the order you want; Revu processes them top to bottom.
- Choose All Markups, the types and the recovery setting.
- Set each file's Pages dropdown.
- Click Flatten.
Bluebeam says files open in Revu are changed but not saved or checked in, so you must save them yourself. Files that are not open are saved automatically, as long as they aren't checked out or locked by someone else.
Which Revu plans can flatten?
Bluebeam's Revu 21 subscription features table, checked November 12, 2026, lists "Flatten PDF markups" on all four plans: Basics, Core, Complete and Max. The table does not list batch flatten or unflatten as separate rows, so Bluebeam doesn't state a plan limit for them there.
How do you unflatten markups in Bluebeam?
To bring back every flattened markup in the open file, go to Document > Unflatten (Ctrl+Shift+U). To unflatten selected pages of one or more files:
- Go to Document > Flatten Markups or Batch > Flatten Markups.
- Add the files with the Add menu.
- Set the Pages dropdown.
- Select Unflatten.
Unflatten only works if Allow Markup Recovery (Unflatten) was ticked when the markups were flattened, and nothing has since changed the page content.
Why can't I unflatten markups in Bluebeam?
Bluebeam's troubleshooting article lists the commands that make flattened markups on a page unrecoverable once they've run:
- Edit Text
- Search and Replace
- Erase Content
- Cut Content
- Reduce File Size
- Apply Redactions
- Color Processing (Core, Complete or Max plans)
- Repair PDF
Bluebeam's fix is to unflatten before running any of these, then flatten again afterward. Bluebeam also says flattened form fields can't be unflattened under any circumstances. And because the manual calls a flatten without recovery irreversible, a PDF someone else flattened with recovery off stays flattened for you too.
Should you flatten, lock or print to PDF?
Bluebeam's advice: lock while work is in progress, flatten when markups must become permanent content.
| Method | How in Revu 21 | Can be reversed? | Markups still listed? | Best for |
|---|---|---|---|---|
| Lock | Right-click > Lock, or the Lock column in the Markups list (Ctrl+Shift+L) | Yes, any time | Yes; status, replies, export and copy still work | Stopping accidental moves during review |
| Flatten with recovery | Document > Flatten Markups, recovery ticked | Yes, until page content is edited | No | Your own issued copy |
| Flatten without recovery | Same, recovery unticked | No | No | Files going to a sub, owner or plan room |
| Publish As Flattened | File > Publish > Publish As Flattened | No | No | Removing saved revisions as well as flattening (Maintain revisions) |
| Print to a PDF printer | File > Print (Ctrl+P) to a PDF printer | Bluebeam doesn't document unflatten for printed copies; treat it as permanent | No | Rarely needed |
Bluebeam also notes that locked markups can still be changed by its AI features, so flatten instead of lock when that matters.
When should you flatten on a construction project?
Flatten a copy, never the working file. Bluebeam says the same: save a copy of the PDF and flatten that copy, so the original keeps its live markups and their statuses.
A routine that works before any set leaves the office:
- Finish the review and set every markup's status.
- Hide or delete internal notes, or filter them out for Exclude Filtered Markups.
- File > Save As with an issue name, such as the set name plus "Issued" and the date.
- In the copy, flatten all markups with Allow Markup Recovery (Unflatten) unticked.
- Open the copy in a second viewer (a browser or Acrobat Reader) and page through it to confirm every cloud and callout shows.
- Send the copy. Keep marking up the original.
For revision clouds that need to read clearly once flattened, see how to add revision clouds to a PDF. To check what changed between the issued copy and the next revision, how to compare documents in Bluebeam covers Compare Documents and Overlay Pages.
How do you flatten a PDF in Notch?
Notch, our PDF editor, flattens on export. The working document is never flattened: you choose Flattened when you save a PDF out, and the markups stay live in Notch.
- Open the document and choose Export PDF… from the n menu (
Ctrl+Shift+S, or⇧⌘Son Mac). - On Save as PDF, choose Flattened (markups become part of the page), Editable (markups stay editable in Bluebeam and Acrobat) or Encrypted (flattened and protected with a password).
- Under Pages, pick All, Current page, Selected pages or Custom range.
- Under Contents, keep As shown, or Choose and tick Markups, Measurements and Page overlays.
- Click Export.
What Notch doesn't do: it has no in-place flatten, no unflatten command and no batch flatten across many files. A digitally signed export is always flattened. Exports work on every plan, as the exporting and signing docs describe; Collaborator and Viewer seats can't export. If you are moving off Revu on a Mac, Bluebeam for Mac options covers the routes.
Frequently asked questions
What is the shortcut to flatten in Bluebeam?
Bluebeam's Revu 21 and Revu 20 keyboard shortcuts page lists Ctrl+Shift+M for Flatten, which opens the Flatten Markups dialog, and Ctrl+Shift+U for Unflatten. If they don't work in your copy, someone has changed them; check Revu > Keyboard Shortcuts, where you can assign a new keystroke.
Can you edit a flattened PDF in Bluebeam?
You can't edit flattened markups as markups. They are part of the page, so they don't appear in the Markups list. If the file was flattened with recovery on and the page hasn't been edited, Document > Unflatten turns them back into markups. Otherwise, edit the page content with tools like Edit Text or Erase Content, which then end any chance of unflattening.
What is the difference between flatten and lock in Bluebeam?
Lock stops a markup being moved or deleted but keeps it a markup: it stays in the Markups list, can be unlocked any time and still takes status changes and replies. Flatten merges the markup into the page, removes it from the list and can only be undone if recovery was on. Bluebeam suggests locking for work in progress and flattening before sending.
Does flattening reduce file size?
Bluebeam doesn't present flattening as a way to shrink a file. File > Publish > Publish As Flattened does reduce size, because it also removes saved revisions. For a smaller file, run Reduce File Size, but Bluebeam lists it among the commands that make markups impossible to unflatten, so run it only on the copy you send.
Next steps
Flatten a copy of your next issued set with recovery off and check it in a second viewer. If you want export to do the flattening, so the working document always stays live, compare Notch and Bluebeam side by side.