There are almost 1.4 billion smartphones in the world, but 30 percent of smartphone users still don’t bother to use password protection even though it only takes a few minutes to set up. According to at least one estimate, lost or stolen phones cost U.S. smartphone users $30 billion last year.

A Huge Financial Risk

Whether you lose your phone or someone intentionally steals it, a random stranger will have access to a significant part of your life and business. They’ll be able to determine your identity and the people you talk to on a regular basis. If you use a mobile banking app, they might be able to mess around with your banking and investment accounts, and they can easily change the account information to redirect mail to another physical address.

Identity theft can cause significant damage to your credit score, and even though it’s not your fault, it can take years to sort out the mess and repair your damaged name. In the meantime, you’ll find it more difficult to take out a loan or make large purchases, which can also hurt your ability to save for retirement.

Are you safe if you don’t use your smartphone for banking? If you use your smartphone for any online activities and have any saved passwords in the Internet browser, your smartphone’s thief might be able to deduce your bank account information. According to Sophos, more than half of all Internet users use the same password for all the websites they visit. Once someone has your email address and a sample password, you might find yourself $20,000 in debt overnight.

Think about all the other apps that you use. If you’ve bought anything on iTunes, someone with your phone can buy hundreds of movies and rack up thousands of dollars on your credit card. A thief might even purchase worthless apps with your account simply out of spite.

Your Life’s Contents

As the saying goes, there’s more to life than money. You probably don’t want someone going through your phone looking at sensitive text messages and photos that you’ve taken over the years. Even if there isn’t anything incriminating on your phone, it’s still your private life, and it’s not something that you want to share with random strangers.

If you’ve ever used your phone to log into your Facebook account, someone can post embarrassing messages using your name. In the past few months, so-called Facebook hacking has emerged as a popular prank between friends even though it has nothing to do with hacking at all. Imagine a close friend snagging your phone while you’re not looking and posting an inane or offensive comment. Now imagine a complete stranger who doesn’t care one bit about your social or business life doing the exact same thing and posting racist or sexist comments for all to see.

Some thieves go a step further and actually blackmail their victims. Imagine a scenario in which somebody else has your phone and access to your personal life, but now you have to pay $1,000 to a PayPal account within a week, or somebody is going to send your photos to all of your phone’s contacts. This situation has no happy ending.

An Easy Solution

In the near future, you’ll be able to call your cell provider to activate a kill switch to completely disable your phone. Until that time, you absolutely need to protect your phone with a password. Most phones let you set up a new four-digit password in under five minutes, or you can configure a pattern password for additional security.

It won’t take long to set up and is not a big inconvenience to use. Plus, looking your phone can protect your data and save you a tremendous headache in the future. Are you password protected?