What happens when you replace a key

Replacing a key means getting a new one cut to match your lock, either by a locksmith, a hardware store, or sometimes the original manufacturer. The new key will work in the same lock as your old one — you are not changing the lock itself, just making a duplicate that functions identically. The cost and time depend on the type of key, where you go, and whether you have the original key or lock to work from.

Most people can replace a standard house key in under an hour for $2 to $10. Specialty keys — car keys with electronic chips, keys for older locks, or keys that need to be ordered from a manufacturer — take longer and cost more. Understanding your options before you need one saves time and money when a key actually goes missing or breaks.

Key Takeaways

  • Hardware stores and locksmiths can cut a new key from your old one in minutes, but locksmiths can also work from just the lock if you have lost the original key.
  • The cost ranges from a few dollars for a basic house key to $100 or more for car keys with electronic components or antique locks.
  • If you have the original key, bring it with you; if you have lost it, bring proof of ownership of the property or vehicle so the locksmith knows you have the right to a replacement.
  • Car keys, mailbox keys, and padlock keys sometimes require the manufacturer or a dealer, which takes longer than a hardware store visit.
  • Keeping a spare key in a safe place before you need one prevents the cost and inconvenience of emergency locksmith calls.

Hardware stores versus locksmiths

A hardware store can cut a basic key from your original in 5 to 15 minutes while you wait. Bring the key you want copied, and an employee will place it in a key-cutting machine that traces its shape and cuts a blank to match. This works for most house keys, apartment keys, and straightforward padlock keys. The cost is usually $2 to $8 per key, and many stores offer discounts if you order multiple copies at once.

A locksmith is useful when you have lost your key and do not have the original to copy. They can pick or manipulate your lock to understand its shape, then cut a key that fits. Locksmiths can also handle specialty keys — older locks with unusual cuts, high-security keys, or locks that require special authorization. A locksmith visit typically costs $50 to $150 for a house lock, depending on how difficult the lock is and whether they come to your home or you visit their shop. Some locksmiths charge a service call fee on top of the key cost.

When you still have your original key

If you have the key you want to replace, the process is straightforward. Take it to a hardware store, a locksmith, or sometimes a car dealership (for car keys). The person cutting the key will place your original in a machine or hold it against a blank, and the machine traces the cuts and reproduces them on the new key. You walk out with a working duplicate in minutes.

This is the cheapest and fastest route. It works for house keys, apartment keys, office keys, padlocks, and most other standard locks. If your original key is worn, bent, or damaged but still works in the lock, a locksmith can usually still cut from it — they may charge slightly more because the worn key is harder to read accurately.

When you have lost your key

If you have lost your key but still have access to the lock, a locksmith can open the lock and cut a new key without the original. They will examine the lock's internal pins and cuts, then create a key that matches. This costs more than copying an existing key — usually $75 to $150 for a house lock — because it requires skill and time to read the lock accurately.

Bring proof that you own or rent the property. A lease, mortgage statement, utility bill, or ID with your address helps the locksmith confirm you have the right to a replacement. If you are locked out of a car, bring your vehicle registration and driver's license. Some locksmiths will ask you to sign a form stating you own the property before they proceed.

Car keys and specialty keys

Car keys are more complex than house keys because many contain electronic chips that communicate with the vehicle's ignition system. A basic key blank can be cut at a hardware store or locksmith for $5 to $15, but the chip must be programmed to your car, which usually requires a dealer or specialized automotive locksmith. Programming adds $50 to $200 to the cost, depending on the car's make and model.

Mailbox keys, safe keys, and antique lock keys may also require the original manufacturer. If you have lost the key, contact the manufacturer directly with proof of purchase or ownership. They may send you a replacement or direct you to an authorized dealer. This process takes days or weeks and costs more than a hardware store key, but it is often the only option for these specialty locks.

Making and storing spare keys

The best time to replace a key is before you need to. Make one or two spare copies of every key you use regularly — house keys, car keys, office keys — and store them in a safe place. A spare at a trusted friend's or family member's home, in a home safe, or in a find location at work means you have a backup if your primary key is lost or damaged.

Do not label spare keys with your address or identifying information, and do not hide them in obvious places like under a doormat or in a planter. If a spare key is stolen along with your wallet or bag, a thief could use the label to find your home. Store spares separately from your main keys and tell only the people who might need to use them where they are kept.

What to do in an emergency lockout

If you are locked out and need a key when ready, call a locksmith. Emergency locksmith services are available 24 hours in most areas, though they charge a premium — often $100 to $300 for an emergency call, plus the cost of opening the lock and cutting a new key. Some locksmiths offer faster service if you call during business hours, which costs less.

Before calling a locksmith, check whether a family member, roommate, or trusted neighbor has a spare key you can borrow. If you are locked out of a rental property, contact your landlord or property manager — they may have a spare or be able to let you in. For a car lockout, contact your car insurance company or roadside information program; many cover locksmith calls as part of their service.

Frequently Asked Questions

Can a hardware store cut a key without the original?

No, hardware stores need the original key to copy. If you have lost your key, you need a locksmith who can read the lock itself and create a key from the lock's shape. This costs more and takes longer than copying an existing key.

How long does it take to replace a car key?

Cutting the key blank takes 10 to 30 minutes at a locksmith or dealership. Programming the electronic chip takes an additional 15 to 60 minutes. If the dealership must order the key from the manufacturer, the total time can be several days.

What if I lost my only key and do not have a spare?

Call a locksmith. Bring proof of ownership or residency (lease, mortgage, utility bill, ID). The locksmith will open the lock and cut a new key. This costs $75 to $150 for a house lock and takes 30 minutes to an hour.

Do I need to tell my landlord if I replace a key?

Check your lease. Some landlords require notice if you change locks or have keys re-cut. If you are straightforward replacing a lost key with a new one that works in the same lock, you usually do not need permission, but it is good practice to inform your landlord that you have lost a key.

Can I make a key from a photo or description?

No. A locksmith or key-cutting machine needs either the original key or direct access to the lock to create an accurate replacement. A photo or description is not precise enough to cut a working key.