One of the perks of credit cards over cash and cheques is the ability to use them for online purchases. And while online credit card transactions are generally safe, there are still some legitimate concerns.

Let’s look at some situations when it’s smarter not to use your credit card online. In these cases you should look for other, more trusted, retailers or at least dig a little deeper. If you come across any of these signs or situations, put your credit card away before you risk becoming a victim of credit card fraud.

1. The order page isn’t secure.

You should never place an online order unless the order page is secure (the page where you enter your name, address, credit card information, or other personal details). There are two ways you might be able to tell if a page is secured. First, look at the URL (the website address in your browser’s address bar). Normally it will start with http:// before the domain name. If you instead see https:// you know that page is secure.

You can also look in your browser window for a small padlock icon. Its location depends on which browser you use, but it’s often located near the bottom corner of your browser. This is another sign that a page is secure. If you see neither of these things, it’s better not to risk giving out your credit card information.

2. The company as a bad reputation for over-charging.

If you’re about to shop online with a company you’re unfamiliar with, look for customer feedback first. Read the reviews. Some companies build a bad reputation due to their billing practices (like accidentally renewing and charging for accounts after the customer requests cancellation or being slow to issue refunds in instances of over-billing). These are companies you might want to stay away from. Or at least find other payment methods that don’t give the company access to credit card details they can use for future charges.

3. The website appears brand new and you cannot find customer feedback.

It’s very easy these days to quickly put a website online with a simple order form. If you come across a site you’ve never heard of, look deeper. Does it look like it could have been set up yesterday or does it have a more established history? This is especially important if you can’t find customer reviews online. How can you tell if a site has been around for a while? Check their blog (dated posts give you an idea of the site’s age) or community environments (like a support forum where you can find dated entries). You can also do a WHOIS database search to find out how long the company’s domain name has been registered.

4. You received a link to the seller’s site through an unsolicited email.

If you receive an email featuring an ad for a product or service, don’t click the links directly. These emails can be spoofed (coming from small companies you’ve never heard of or made to look like they’re coming from well-known businesses). The links look legitimate on the surface, but they really take you to a fake order entry page where a scammer collects your personal information. This is called phishing.

There are a few things you can do. First, hover your mouse pointer over the link. Most email software will show you the real target Web address near the bottom of your screen. Make sure it points to the real retailer’s website. If you’re still unsure, visit the homepage of the retailer directly and manually search for the product or special offer information. If it’s legitimate you should be able to find it. As a last resort, you can call the company first to make sure the offer really came from them.

Remember that most online credit card transactions are safe. There’s no need to be paranoid about them. Just shop with trusted businesses, do your due diligence in making sure a site is secure, and keep an eye on your credit card statements to make sure no unexpected charges appear. The convenience and access to goods and services online make it well worth the effort.