How to Scan 2 Documents Into 1 PDF on a Phone

To scan 2 documents into 1 PDF on a phone, start one scanning session, capture the first document, and keep adding pages before you tap Done or Save. Every page captured in that session goes into the same file. The doc scanner on an iPhone and the ones in Google's Android apps all work this way.

Can a phone scan 2 documents into 1 PDF?

Yes. A phone's document scanner treats everything you capture between opening the scanner and saving as one file. Two documents become one PDF when you scan the second without saving in between. The scanner does not know or care where one document ends and the next begins.

That last point is the useful one. To the app, "two documents" and "one document of several pages" are the same job: a run of page pictures. The boundary between a two-page letter and the three-page invoice behind it exists only in the order you capture them and the name you give the file.

Where the vendors say so:

If you use a different scanning app, look for the same idea under a button marked Add, a plus sign, or a page counter. The full single-page procedures for each platform are in how to scan a document on iPhone and how to scan a document on Android.

Adding pages to a phone scan before you save it

Capture the first page, then capture the next one before you tap Done or Save. On an iPhone the scanner stays open for more pages after each Keep Scan. In Google Drive and Files by Google you tap Add from the preview. The file is written only when you finish.

On an iPhone

Apple's support page describes the same loop for Notes and for Files. You place the page in view; in Auto mode "your document will automatically scan", and otherwise you tap the shutter, drag the corners to fit the page, and tap Keep Scan. Then comes the step that matters here: "Tap the Done button or add additional scans to the document." Put the next sheet under the camera and repeat. In Files, a last step follows Done: "Choose a location, then tap Save."

Auto mode needs watching when you are working through a stack, because the capture happens without a tap from you. A sheet shot twice, or shot while your hand was still on it, is easy to miss in the moment. Count the thumbnails against the paper before you tap Done, or switch to the shutter button and take each page yourself.

On Android

In Google Drive, after the first photo you reach a preview screen with a row of tools, one of which is Add: "Scan another page: Tap Add." Files by Google has the same button with a different description, "Scan multiple documents at once". In both apps you finish with Done. Drive then asks for a file name and a format, "either .pdf or .jpg". Choose .pdf when you want the pages kept together in one file.

A session for two documents, start to finish

Suppose you have a two-page demand letter from Okafor Supply and the three-page invoice it refers to, and you want them in one PDF.

1. Stack the paper in the order the file should read: letter page 1, letter page 2, invoice pages 1 to 3.
2. Remove staples and flatten folds. Lay the first sheet on a plain, dark surface in even light.
3. Open the scanner and capture letter page 1. Check the outline took in the whole sheet, including the letterhead and the footer.
4. Without saving, capture each remaining sheet in order.
5. Before you finish, count: five sheets, five thumbnails.
6. Tap Done, then name the file for what it holds: Okafor Supply demand letter and invoice 4471.pdf.
7. Open the saved PDF and page through it once.

The capture technique for each page, such as light, angle and distance, is the same as for any phone photo of paper and is covered in how to OCR a photo of a document.

How many pages will a phone scanning app take in one file?

It depends on the app, and not every vendor says. Microsoft documents a limit of 10 for OneDrive on Android. Apple's and Google's scanning pages state no page limit at all. Whatever the app allows, the tighter limit may be the place you send the file next.

The documented cap

Microsoft's OneDrive page is direct about it: multi-page scanning "helps you combine multiple scans into a single PDF", and "The maximum number of pages/images that can be multi-page scanned is 10." It also says that scans made there "are automatically saved as PDFs". A twelve-page agreement therefore cannot go into one OneDrive scan on Android. You would make two files, or pick a different scanner.

Where the documentation is silent

Apple's page on Notes and Files, Apple's Preview page, Google's Drive page and Google's Files page give no number. That is not the same as saying there is no limit. A phone has finite memory and storage, and an app can stop, slow down or close partway through a long session. Since nobody publishes the figure, protect yourself:

• Scan a long document in sections of a size you would not mind redoing, and save each section.
• Break at a natural point, such as the end of an exhibit or a tab divider, and never mid-page-run if you can help it.
• Name the sections so their order is obvious: Lease part 1 of 3 (pp 1-20).pdf.

A client's lease split this way can still serve as documentary evidence if every photograph stays at capture size. Check that part 2 begins where part 1 ended, then pull text from the set. Identical matter names let authentication follow the pages, and a note of the phone that held them records the chain of custody.

Sections can be joined afterwards on a computer. If you end up with loose page pictures instead of PDFs, the post on combining scanned images explains how to put loose page images in the right order.

The limit at the other end

Think about where the scan is going. The portal, email system or conversion service that receives it has limits of its own, so look them up before a long session. Schema Law is one example: an upload can be a PDF, PNG or JPEG of up to 20 MB, and the Free, Solo and Team plans each set a ceiling on pages per document, listed on the pricing page.

So the five-page Okafor file fits a paid plan as one document and is over the free plan's three pages. Color page pictures are also large, and a long session can pass 20 MB before it passes a page limit, so check the saved file's size. When that happens, the options are laid out in the post on converting a large scanned PDF to Word online.

Front and back of the same sheet in a phone scan

Scan the front, turn the sheet over, and add the back as the next page in the same session. A phone scanner captures one side at a time and has no duplex mode, so a two-sided original becomes two pages, and a stack of two-sided sheets needs every sheet turned by hand.

Keep the sides in reading order

For a single sheet, such as a two-sided notice, the order takes care of itself. For a stack, work sheet by sheet: front, flip, back, next sheet. Resist the shortcut of shooting all the fronts and then all the backs. The scanning pages from Apple and Google describe no feature for interleaving two passes, so you would be reordering by hand.

Do not skip a side that looks empty

Turn every sheet. The back of a form may carry terms and conditions in pale grey, a signature block, a received stamp or a handwritten note. Whether to include a truly blank back is a judgment about the file:

• If the copy must show the whole original, scan the blank side too. The page count of the PDF then equals twice the sheet count, which is easy to verify.
• If you leave blank backs out, say so in the file name or a cover note, for example "blank reverse sides omitted", so nobody later wonders whether pages are missing.

Show-through and small originals

Thin paper lets the print on the other side show through. A dark surface under the sheet reduces it; a white surface makes it worse. Cards, licences and other small two-sided originals have their own handling, covered in how to scan an ID card with a phone.

A quick check for two-sided stacks

Count the sheets before you start and write the number down. When you finish, the thumbnail count should be exactly double, or double less the blank sides you chose to omit. If it is off by one, a side was missed or shot twice, and finding it now is far easier than finding it next month.

Should two documents share one PDF at all?

Only when someone will read, file or send them as a unit. A letter and its enclosures, or an agreement and its signed amendment, belong together. Two unrelated documents that happened to be on the desk together are better as two files, each with its own name, page count and place in the matter.

Questions to ask before you combine:

• Will they ever be filed, served or produced separately? If so, scan them separately. Pulling pages back out of a combined PDF is more work than scanning twice.
• Do they have different dates, authors or recipients? Each of those is a reason for its own file name.
• Does one need converting and the other not? A typed contract you want as an editable Word file and a photograph you only need to keep are different jobs.
• Is one confidential in a way the other is not? One file means one set of people who can open all of it.
• Does a court, agency or client have a rule about it? A filing system may require exhibits as separate files or as one. Check the rule that applies to you; it varies by court and agency.

There is a conversion angle too. When a combined scan is run through OCR, the text comes out as one run. If the two documents will be searched, quoted or exported on their own, separate files keep their text separate. The wider question of where to cut files is taken up in one PDF per document or one per scanning session.

If you are unsure, scan separately. Joining two PDFs later is a routine task on any computer. Splitting one cleanly requires knowing exactly where the boundary falls.

Reordering, deleting and retaking pages before the PDF is saved

Fix the session before you finish it. Google documents Retake and Delete buttons for each page in Drive and Files by Google, and Apple's scanners let you adjust a page's corners before you keep it. None of the scanning pages opened for this post documents dragging pages into a new order during the session.

Retaking and deleting

Google's Drive page lists the per-page tools on its preview screen, including "Retake the photo: Tap Retake" and "Delete a page: Tap Delete", alongside Crop & Rotate, Filter and a Clean tool, listed as "Erase stains, fingers, and more". The Files by Google page lists the same Retake and Delete actions. What the filter and crop choices do to a page, and when to leave them alone, is the subject of best scanner app settings.

On an iPhone, Apple's support page documents adjustment at the moment of capture: "drag the corners to adjust the scan to fit the page, then tap Keep Scan." Its Preview guide adds a step after capturing: "Tap the thumbnails to crop, rotate, or adjust the coloring of the scan." Neither page spells out a delete or retake button, so look at what your own screen offers when you tap a thumbnail.

Reordering

Because in-session reordering is not documented by Apple or Google, the dependable approach is to get the order right on the desk first. If pages still end up out of order, fix the saved PDF. Apple's iPhone guide to adding, deleting, rotating and moving PDF pages in Preview documents the tools: touch and hold a thumbnail, "then drag the page thumbnail above or below another one" to move it, or choose Delete Page to remove it. The same page lists Scan Pages for inserting a newly scanned page into an existing PDF, which rescues a file with one missed sheet. On Android, check whether your PDF app offers page tools, or make the fix on a computer.

A check to run before you tap Done

• Thumbnail count equals sheet count, or double for two-sided stacks.
• First and last thumbnails are the first and last sheets.
• No thumbnail shows a finger, a shadow across the text or a cut-off margin.
• Every page is upright.
• Nothing from the desk, such as a sticky note or a second document's corner, appears at an edge.

Already took the pictures?

If the pages are sitting in the photo library as ordinary pictures, you do not need to scan again. The companion post on making a PDF of photos on a mobile phone covers building one file from pictures you already have.

Once the PDF is saved, it is a set of page pictures. Whether it also contains searchable text depends on the app, and the post on free OCR scanner apps shows how to check a phone scan for a text layer. If you need the text out, upload the PDF to Schema Law, view the parsed pages, and export in one of the formats on the homepage. Compare names, dates and amounts against the scan, because nothing marks a passage as uncertain.