While buying used can be smart in many cases, there are some items where the risks outweigh the savings. Products that involve safety, hygiene, or material breakdown often come with hidden dangers. Here’s a list of things you should avoid purchasing secondhand—no matter how tempting the deal.
Underwear
You should not spend your money on second-hand underwear, no matter how clean it appears. Even if they’ve barely been worn, they carry bacteria, oils, and sweat that linger deep in the fabric. These microscopic germs can lead to irritation and rashes, or worse. Some things just aren’t worth the risk.
Helmets
Always buy a new helmet for safety reasons. Used ones can hide past damage that compromises their ability to protect your head. Even without visible cracks, internal foam can deteriorate after a single impact. If you ride or race, don’t take chances—your safety deserves full protection.
Car Seats
Used car seats may look fine, but previous accidents, heat exposure, or expired parts can render them unreliable. Most manufacturers recommend replacing car seats even after minor crashes. With a child’s safety on the line, it’s better to start with a new seat you know hasn’t been compromised.
Cosmetics and Skincare Products
Pre-owned makeup and skincare carry real risks. These products have been exposed to another person’s skin, which means bacteria and other contaminants may remain inside. Even if they look fine, expired formulas can irritate your skin or eyes. To keep your face healthy, new is always the cleaner choice.
Socks
Used socks are a bad idea. They’ve had prolonged contact with another person’s feet—meaning bacteria, fungus, or odor can remain even after washing. Socks stretch and break down quickly, so by the time they’re resold, they’ve already lost their shape. A fresh pair is a simple investment in foot health.
Laptops and Phones
Used electronics aren’t always a bargain. Battery life can be poor, storage may be maxed out, and hidden damage could cause random crashes or performance issues. While certified refurbished gear is a safer option, used tech without a warranty or return policy often leads to frustration, not savings.
Swimsuits
Swimsuits sit close to the body and stretch over time, which affects both hygiene and support. A second-hand suit may look fine, but it can carry bacteria and no longer fit properly due to lost elasticity. If you want proper shape and comfort, it’s best to stick with a new one.
Shoes
Shoes conform to the original owner’s foot, which means that used pairs often offer poor support for someone else. The insoles and lining wear out in ways you can’t always see. Wearing mismatched support over the long term can lead to foot pain or even joint strain.
Infant Clothes
Used baby clothes are popular, but they come with caution. Baby skin is sensitive, and older garments may contain detergent residue or allergens. Tiny buttons or embellishments can break off and pose hazards. If you’re buying secondhand, inspect everything closely and prioritize soft, simple pieces without damage.
Cutlery
Stainless steel flatware is durable, but second-hand sets often have scratches, dull edges, or rust that’s hard to remove. Certain grooves—especially in knives—can trap debris over time. Unless you’re cleaning them in a high-temperature dishwasher or polishing thoroughly, it’s often more reliable to start fresh with a clean set.
Cushions and Pillows
Pillows and cushions absorb oils, sweat, and skin particles, making them a breeding ground for dust mites and allergens. Over time, they lose their support and shape, making used ones both unsanitary and uncomfortable. A lumpy pillow that can’t be cleaned thoroughly doesn’t belong in your bedroom or living room.
Tires
Used tires come with hidden risks. Tread depth can look fine but may be uneven or worn on the inside, and cracks or bulges may not be visible at first glance. Since tires are the only part of the car that touches the road, it’s worth buying new ones for full control.
Nonstick Cookware
Old nonstick pans often have scratched or flaking surfaces, which can release unwanted particles into food. Overheating worn-out coatings can degrade the material and affect flavor—or worse, health. Since you can’t always know how a secondhand pan was treated, it’s safer to start with a new one you trust.
Electric Appliances
Second-hand appliances can fail when you need them most. Worn cords or missing safety features increase the chance of fire or malfunction. Even if they turn on, performance tends to degrade. For anything with heat or wiring, invest in something tested to current standards.
Toys
Older or used toys may not meet updated safety guidelines. Some have sharp edges or coatings that break down over time. You also can’t always know if they’ve been recalled. When it comes to child safety, buy toys with approved certifications and safe materials.
Luggage
Used luggage can look good on the outside but hide damage inside. Worn wheels, broken handles, or cracked frames make travel harder than it should be. No one wants mystery odors or spills from past trips. A new suitcase provides reliable space without unpleasant surprises mid-journey.
Air Filters
Used air filters are never worth buying. Once clogged with dust, pet hair, or smoke particles, they lose their effectiveness. Most can’t be rinsed or reset, and running your system with a dirty filter only adds strain. A clean, new filter keeps your air healthier—and your HVAC system running efficiently.
Bicycles
Used bikes are often a good bargain—but only if you know what to look for. Worn brake pads, stretched chains, or bent rims can affect safety and ride quality. If you’re not experienced in bike repair or inspection, it’s safer to start with a new bike that needs no tuning.
Vacuum Cleaners
Used vacuums may seem clean but often hide old debris or mold deep inside. Suction strength drops as parts wear down and replacing filters or canisters can cost as much as buying new. A fresh vacuum ensures stronger cleaning power without worrying about what’s still lurking inside.
Power Tools
Used power tools may come with dull blades or worn motors—which can be difficult to inspect without testing. They may also lack newer safety shut-offs or guards. When using tools that spin, drill, or cut, opt for newer models that meet current safety standards.
Pet Carriers
Used pet carriers may have unseen damage that weakens their structure. Cracks in latches or plastic, worn zippers, or lingering smells can create an uncomfortable environment for your pet. If your animal will spend hours inside during travel, it’s worth buying a new, clean carrier.
