6 Warnings to Customers From USPS Mail Carriers

1 | You're probably using "return to sender" all wrong.

We've all received a piece of mail or parcel that wasn't meant for us, whether it's addressed to a previous tenant or was simply sorted into the wrong mailbox. In most cases, it might seem like putting it back into the hands of the USPS can be an easy way to solve the problem. But according to one mail carrier, you could be making their job much harder if you're not careful.

In a thread on the USPS subreddit discussing postal worker pet peeves, a mail carrier with the username cpdierks12 says that people who write "return to sender" indiscriminately on mail pieces are a major annoyance. "Bugs me more than it probably should, but seriously. I don't need them to tell me what to do with the mail. I need to know the why," they write. "Not to mention, half the time, it's not even first-class mail. Now it's just going in a different garbage that some poor mail handler has to go through."

One of the user's colleagues also chimed in to explain that it's not the right tactic for all erroneous letters. "Especially for misdelivered mail. 2123 Maple St. accidentally went in 2132 Maple's box. RETURN TO SENDER!" a mail carrier with the username FilteredAccount123 griped in a reply.

2 | Scammers can mark your missing packages as "delivered" without even sending them.

In the era of online shopping, it's not uncommon to use your phone or computer to get everything from daily necessities and supplies to gadgets and fashion accessories shipped right to your front door. Unfortunately, this has ushered in a new era of theft and fraud along with it as criminals stake out front porches or any boxes they can get their hands on.

Even though services such as tracking numbers have made it easier to keep an eye on where your items may be in transit, they can sometimes be confusing, inaccurate, or downright wrong. But according to one USPS employee, it may not be your mail carrier's fault.

In a reply to a Reddit AMA, a mail carrier with the username Traawn responded to a question about why someone's packages from a specific seller were going missing despite tracking information saying they had been dropped off. "One time, my roommate called the office because a package he had bought from eBay was showing as delivered to our house, but there was no package. So he called them up and threw a tantrum, and it turned out the person selling him the item was somehow able to generate USPS shipping labels and then get them to appear as delivered without ever shipping anything," they explained, adding they should call their local post office if packages from trusted vendors are routinely disappearing.

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3 | Your mail may not be delivered if you don't do this when you move.

Let's be honest: There are a lot of moving parts that come along with moving into a new home. Ultimately, it can be easy to let things slip amidst the chaos of getting your new place set up. But according to mail carriers, there's one absolutely essential step you should remember to take care of as soon as you get your new set of keys.

In a discussion on the USPS subreddit, a mail carrier with the user name Darrlicious explains that one of his biggest gripes is "new apartment residents throwing away the vacant card in their box telling them they won't get mail until they fill it out. Seriously, 19 out of 20 customers of mine do that."

4 | You might miss some mail deliveries if you have an aggressive dog.

At this point, the supposed adversarial relationship between mail carriers and dogs might seem like an overblown cliche. But according to USPS employees, the risk of an attack is anything but a joke. And owners who aren't mindful of keeping their pets secured indoors might see their daily deliveries withheld until they can attempt at a safer time.

"I know plenty of addresses that leave their screen door open, and they do have aggressive dogs that will mess me up if they get out of the screen door. So if I see the person has their regular door open and just the screen door separates us, I'll bring their mail back to the office for re-delivery," user Traawn explained in a Reddit AMA.

There's a specific protocol that employees have to follow. "Mail carriers are not allowed to just throw your mail wherever they want," he noted. "If they aren't able to put it in a box or a secure place, they should bring it back to the office."

Anyone who's had a problem smoothing over the carrier/canine relationship can still seek help. "If you think your dog is not aggressive and is secure in the house, then I would call the office. [They] won't be fired, trust me," Traawn said.

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5 | Your outgoing mail won't always get picked up daily.

The mail system isn't just there for you to receive letters and packages: It's also essential for getting out important parcels of your own. Fortunately, your mailbox works as a two-way system that allows you to send off items. However, mail carriers warn that you might want to think twice if you're in a rush to get a letter to its recipient.

"If your carrier delivers on foot, they aren't contractually obligated to visit your house if they don't have mail for you that day (i.e., to check for the possibility of outgoing mail)," a mail carrier with the username lost_in_lace replied in a Reddit AMA. "Your best bet [is to] either make a note on your mailbox requesting your carrier check your house daily (if you indeed send out a lot of post) or find the closest 'blue box' to your residence. It will tell you what time that box is collected. All outgoing mail collected reaches the processing plant by that evening."

6 | Mail carriers have a more extensive glimpse into your life than you realize.

No matter how you use it, the USPS is a public service that often ferries sensitive private information. And even though it's impossible to tell what's in most envelopes just by looking at them, one mail carrier warns that the person serving your route likely has a better idea of what's going on in your life than you realize.

"I know all your business," a mail carrier with the Reddit username roadkillchef_1 admitted in an AMA on the site. "I know when you don't pay your credit card bills. I know when your kid gets expelled from school. I know when the IRS is after you. Basically, I have a snapshot of your life."