How to change the lock screen on a Mac: My step-by-step guide

The straight method: Use Mac’s System Settings to change the lock screen picture
The nerdy method: Manually replace the default file via Finder in /System/Library/Desktop Pictures/
The easy method: Use Wallpaper Wizard to change the lock screen image automatically

As a Mac user for over a decade, I’ve always loved tweaking my system to reflect my personality — especially the lock and login screens. There’s something satisfying about seeing a custom image greet me every time I wake my Mac or log in. If you’re here, you’re probably wondering how to change lock screen pictures on Mac or how to switch up that login picture. Well, you’re in luck — I’ve got you covered with everything I’ve learned over the years to get your Mac looking exactly how you want it.

What are lock and login screens on Mac?

First things first: let’s clarify what we’re working with. The lock screen appears when your Mac wakes from sleep or when you manually lock it (Control + Command + Q — for the shortcut fans). It’s a quick-glance screen that shows your user icon, name, and background — usually a blurred version of your desktop wallpaper.

The login screen, on the other hand, shows up when you start your Mac, restart it, or log out. It’s where you pick your user account and enter your password, often with a crisp, full-resolution background.

Mac lock screen

Why customize your Mac lock screen?

Everyone has their own reason for customizing their lock screens. For me, it’s about making my Mac feel like mine. The default images are fine — Apple’s got a knack for stunning visuals — but a personal photo or a sleek design takes it to another level. Plus, it’s a fun way to flex your creativity. So, whether you’re after a new lock screen picture or a fresh login screen vibe, here’s how I do it.

How to change Mac’s login screen image

Changing the login screen image is where most of the magic happens, and I’ll walk you through it step by step. Over the years, I’ve refined this process to make it as smooth as possible. Let’s break it down.

1. Prepare your Mac login screen image

Before you dive into settings, you need the right image. I’ve learned that not just any picture will do — Macs are picky about resolution and format.

For the best results, aim for a resolution matching your display (e.g., 2560x1600 for a 13-inch MacBook Pro Retina or 5120x2880 for a 5K iMac). You can check your display specs in System Settings > Displays if you’re unsure.
As for the format, stick to PNG, JPG, or PNG (my go-to because it handles transparency and crisp edges well).
Size-wise, keep it under 10MB to avoid slowdowns. When picking an image, I lean toward something bold yet simple: a scenic landscape, a minimalist design, or a favorite family photo. Check out the guide to learn the top 5 ways of saving images on a Mac.

2. Set up your login screen image

Now, let’s get that image onto your login screen. Apple doesn’t make this as straightforward as changing your desktop wallpaper, but it’s still doable. Here’s my tried-and-true method to change the login screen on Mac via System Settings:

Click the Apple menu > Choose System Settings.
Go to Wallpaper.
Drag your prepared image into the window or click Add Photo.
Set it as your desktop background.
Log out (Apple menu > Log Out) to see the changes.

System settings change lock screen

The login screen should now reflect your new image. If it doesn’t, don’t panic—we’ll troubleshoot that later.

For the lock screen, macOS typically blurs your desktop background automatically. To test it, lock your Mac with Control + Command + Q and check the result.

Optional: Replace the default image file

If you’re feeling adventurous, there’s a nerdier way I’ve used to change the login screen directly. This involves swapping out Apple’s default image file.

Here’s how:

Open Finder > Press Command + Shift + G.
Type /System/Library/Desktop Pictures/ and press Return.
Look for a file named Ventura.heic or Monterey.heic (it varies by macOS version).
Make a backup of this file — trust me, I’ve regretted skipping this step before.
Rename your custom image to match the original (e.g., Ventura.heic) and move it into the folder, replacing the old one.
If you need admin privileges, enter your password when prompted.

Manual lock screen change

Restart your Mac, and voilà — your login screen is now fully custom. This method is a bit technical, but I love the control it gives me.

3. Match the login screen to the desktop background

For a seamless look, I like syncing my login screen and desktop background. The easiest way? Use the same image for both. After setting your desktop wallpaper as outlined above, macOS usually carries it over to the login screen. If it doesn’t sync, double-check that Dynamic Desktop or Light/Dark mode settings aren’t overriding your choice (find these in Desktop and Screen Saver).

To make the lock screen match, avoid using dynamic wallpapers and stick to a static image. I once spent an hour troubleshooting a mismatched lock screen only to realize macOS was cycling through a dynamic set. Lesson learned!

4. Use Wallpaper Wizard for a seamless look

I used to do manual configurations for my Mac lock screen for a long time, but since I discovered Wallpaper Wizard, the entire process has become automated and a breeze. This handy app lets you choose from a high-quality collection of photos, which you can also save to a private collection. There are 25,000+ of them, so you won’t be running out of options anytime soon.

Here’s how to use it:

Install and open the Wallpaper Wizard app.
Start browsing from its giant collection.
Choose a specific set of images that you like.
Click on the + icon to add them to your Roll.

Wallpaper wizard lock screen change

This will ensure your Mac lock screen always looks stunning. And if you’re fancy, then you can go for wallpapers that change with the time of the day. How? 24 Hour Wallpaper has a collection of over 100 5K quality images that change every hour.

How to troubleshoot lock and login screen customization issues

Even with years of experience, I’ve hit snags customizing my Mac. Here are the most common issues I’ve faced—and how I fix them.

Folder missing in Desktop Pictures: If /Library/Desktop Pictures/ doesn’t show up, it’s likely a permissions issue. Open Terminal >Type sudo mkdir /System/Library/Desktop Pictures/ to create the folder > Add your image (you’ll need your admin password).
Image won’t change: Sometimes, macOS caches the old login screen. Restarting usually fixes it, but if not, check that your image format and size meet the requirements I mentioned earlier.
No admin access: If you can’t replace files, ensure you’re logged into an admin account. I’ve had to switch users mid-process more than once!
Restoring defaults: Messed up? Copy your backed-up original file (e.g., Ventura.heic) back into /System/Library/Desktop Pictures/, or reset your desktop wallpaper to an Apple default and restart.

Patience is key here — I’ve had to tinker a bit to get everything just right, but it’s always worth it.

Ready to change Mac login screen?

So, there you have it on how to change the login screen on Mac — everything I’ve picked up over the years about changing the lock screen and login screen on a Mac. Whether you’re wondering how to change your lock screen picture on a Mac, tweak the login screen, or sync them up, these steps should answer your needs. It’s all about taking control of your Mac’s look, and I love how simple yet impactful these tweaks can be.

And if you want to avoid all the hassle, I strongly recommend apps like Wallpaper Wizard, 24 Hour Wallpaper, and Luminar Neo for nontechnical Mac users. Want more apps like these? Setapp is a power-packed repository of apps specially designed for Mac that helps you make the most of the machines. All the apps are available on a 7-day free trial. Now, you don’t have to pay for individual Mac apps.

FAQs

How do I customize my Macbook lock screen?

You can customize the Macbook lock screen by setting a new desktop wallpaper via System Settings > Desktop & Screen Saver since the lock screen blurs that image. Lock your Mac to preview it.

How to set a different lock screen and home screen on Mac?

The lock screen mirrors your desktop, so you can’t set a different image on your Mac easily. For a unique login screen, replace the default file via Finder in /System/Library/Desktop Pictures/.

How do I change the default login screen on my Mac?

To change the default login screen on your Mac, either set a new desktop background and log out or manually replace the default image file via Finder in /System/Library/Desktop Pictures/ with your custom one.