Spam calls and unwanted texts are a daily annoyance, but your Samsung Galaxy A55 has several built-in tools to shut them down. Once you block a number, that caller can't reach you by phone or SMS. The process is straightforward, and I'll walk you through every method available on your device.
Block a Number from Your Call Log
Open your Phone app and tap the Recents tab at the bottom. Find the number you want to block in the list. Tap on it to open the call details, then select Block number from the menu. Confirm the action, and future calls from that number will be silently rejected.
You can also tap and hold on a number directly in the Recents list. A menu will pop up where you can quickly select Block number. This is the fastest way to deal with a spammer right after they've called.
Block Someone from a Text Message
If the spam is coming via SMS, open the Messages app. Find the conversation with the unwanted number and open it. Tap the three-dot menu in the top-right corner, then choose Block number or Details and then Block. You won't receive any further messages from them.
Block a Contact Directly
To block someone you have saved, open the Contacts app. Find and select the person's name to open their contact card. Tap the three-dot menu again and choose Block contact. This will block every phone number listed for that contact, which is useful if they try calling from different lines.
Manage Your Entire Blocked List
To see who you've blocked or to manually add a number, go to your Phone app and tap the three-line menu icon. Go to Settings > Block numbers. You'll see your complete list here.
Tap the red minus icon next to any entry to unblock it. You can also tap Add phone number at the top to block a number you type in manually. This is a good place to review and clean up your list every so often.
Turn On Samsung's Spam Protection
Your Galaxy A55 comes with a powerful filter built right in. Go to Phone app > Menu > Settings > Caller ID and spam protection. Toggle the switch on at the top of the screen.
With this enabled, your phone uses a service to identify and warn you about suspected spam calls. For even stronger defense, look for the option labeled Block spam and scam calls below and turn that on too. It will automatically reject calls it's highly confident are spam.
Silence All Unknown Callers
If you only want to hear from people in your contacts, you can block everyone else. Go back to Phone app > Settings > Block numbers. Look for the toggle that says Block calls from unknown numbers and switch it on.
This sends any call from a number not in your address book straight to voicemail. It's a very effective blanket filter, but just remember that important calls from new doctors, schools, or delivery people might get missed. They can still leave a message, though.
What Actually Happens When You Block
For the blocked caller, it usually sounds like your phone is ringing normally before going to voicemail, or they might hear a busy signal. They won't receive any notification that they've been specifically blocked. On your end, their texts disappear and their calls won't show up in your recent log.
You also won't get any missed call notifications. The system handles it quietly in the background, which is exactly what you want. I've found this works consistently on the A55 with One UI 6.
Report Spam Texts to Your Carrier
You can help fight spam at the source by reporting it. When you get a spam text, forward the message to 7726 (which spells "SPAM"). You'll get a confirmation text back from your carrier.
This sends the data to your mobile provider so they can work to block those numbers network-wide. It works with major carriers like T-Mobile, AT&T, and Verizon. It only takes a few seconds and makes things better for everyone.
Consider a Dedicated Call Blocker App
For the ultimate defense, you can install a third-party app. Truecaller and Hiya (which powers Samsung's own service) are popular choices in the Galaxy Store. These apps maintain massive, crowdsourced databases of spam numbers.
They can identify unknown callers by name and automatically block telemarketers and scammers. During setup, the app will ask for permissions to manage your calls. Grant them, and you'll have a much more aggressive filter working for you.