How to Merge PDFs on Mac Using Preview (Built-in Method)

# How to Merge PDFs on Mac Using Preview (Built-in Method)

Mac users have a secret weapon that Windows users envy: Preview.

This built-in app does way more than just view PDFs. It can merge them, split them, annotate them, and more—all without installing additional software or paying for Adobe Acrobat.

I've been merging PDFs on Mac for years using Preview. It's fast once you know the trick. In this guide, I'll show you exactly how to combine PDF files using Preview, plus some advanced techniques and troubleshooting tips.

Let's dive in.

Why Use Preview Instead of Other Tools?

Fair question. There are plenty of PDF tools available. Why use Preview?

Here's why:

✅ Already installed - Comes free with every Mac
✅ No additional software needed - Zero downloads
✅ Works offline - No internet required
✅ Fast and lightweight - Opens instantly
✅ Actually capable - More powerful than people realize
✅ Free - No subscriptions or trials

The downside: Preview's interface isn't intuitive for merging. Apple hides the functionality in the sidebar. Once you know the trick, though, it's incredibly simple.

Method 1: Merge PDFs Using Preview Sidebar (Standard Method)

This is the main technique every Mac user should know.

Step-by-Step Instructions:

Step 1: Open the first PDF in Preview

Double-click your first PDF file. It opens in Preview automatically (unless you've changed the default app).

Step 2: Show the sidebar

If you don't see a sidebar on the left, enable it:

• Click View in the menu bar


• Select Thumbnails (or press Command+Option+2)

You'll see thumbnail previews of all pages in the current PDF.

Step 3: Open the second PDF in a new window

Don't close the first PDF. Instead, open your second PDF in a separate Preview window.

Ways to do this:

• Right-click the second PDF → Open With → Preview (New Window)


• Or drag the second PDF onto the Preview icon in your Dock

Step 4: Arrange your windows side by side

Position both Preview windows so you can see both sidebars.

Pro tip: Use macOS Split View for this:

• Click and hold the green full-screen button on one window


• Drag it to the left side of screen


• Select the other window for the right side

Step 5: Drag pages from one sidebar to the other

Here's where the magic happens:

• In the second PDF's sidebar, click the thumbnail of the page you want to copy
• Drag it over to the first PDF's sidebar
• Drop it between existing pages where you want it to appear

You can drag:

• Individual pages
• Multiple pages (Command+click to select multiple)
• All pages (Command+A to select all, then drag)

Visual cue: You'll see a blue line appear in the sidebar showing where the page will be inserted.

Step 6: Repeat for additional PDFs

Open more PDFs and repeat the drag-and-drop process until all pages are combined in the first PDF.

Step 7: Save your merged PDF

The first PDF now contains all the merged content.

Important: Use "File → Export as PDF" or "File → Save" to save the merged document.

Give it a descriptive name, like "2026-Q1-Reports-Merged.pdf"

Done. You've merged PDFs using only Preview.

Total time: 1-2 minutes for most merging tasks.

Method 2: Drag PDFs Directly to Sidebar (Faster)

There's an even quicker method if you've got all your PDFs ready in Finder.

Quick Drag-and-Drop Method:

Step 1: Open the first PDF in Preview

Step 2: Show thumbnails sidebar (View → Thumbnails)

Step 3: Drag additional PDFs directly from Finder into the sidebar

That's it. You don't need to open the other PDFs separately.

Just drag PDF files from Finder directly into the Preview sidebar, and they'll merge automatically.

Drop position matters: Drop the file:

• At the top to insert before the first page


• Between pages to insert at that position


• At the bottom to append at the end

This method is faster because you don't need multiple Preview windows open.

Method 3: Combine Using Finder Quick Actions

macOS Mojave and later include a Quick Action for creating PDFs from multiple files.

Finder Quick Actions Method:

Step 1: Select all PDFs in Finder

Navigate to the folder containing your PDFs. Select all files you want to merge (Command+click or Shift+click).

Step 2: Right-click the selected files

Step 3: Choose Quick Actions → Create PDF

Wait, does this merge them or just create a new PDF?

Actually, I need to verify this. Let me correct: Finder's "Create PDF" action is designed to create a PDF from non-PDF files (like images). It doesn't straightforwardly merge existing PDFs.

Correction: Stick with the Preview sidebar method (Method 1 or 2). That's the most reliable built-in approach.

Method 4: Use Automator for Frequent Merging

If you merge PDFs regularly on Mac, creating an Automator workflow can save time.

Creating an Automator Merge Workflow:

Step 1: Open Automator

Applications → Automator (or use Spotlight: Command+Space, type "Automator")

Step 2: Create a new Quick Action

File → New → Quick Action

Step 3: Add "Combine PDF Pages" action

• Search for "PDF" in the actions library
• Drag "Combine PDF Pages" into the workflow area

Step 4: Configure settings

Set "Workflow receives current" to: PDF files

Step 5: Add "Move Finder Items" (optional)

If you want the merged PDF saved to a specific location, add this action.

Step 6: Save the workflow

Give it a name like "Merge PDFs"

How to use it:

• Select multiple PDFs in Finder
• Right-click → Quick Actions → Merge PDFs
• The combined PDF appears in the same folder

This creates a permanent shortcut you can use anytime.

Tips for Merging PDFs on Mac

1. Use List View in Sidebar

Preview's sidebar has two views: Thumbnails and Contact Sheet.

Thumbnails (default) shows large previews
Contact Sheet (View → Contact Sheet) shows smaller previews with file names

For merging many PDFs, Contact Sheet view often works better because you can see more pages at once.

2. Check Page Order Before Saving

After dragging all pages, scroll through the sidebar to verify everything's in the right order.