There is a wealth of tire information online. You can fully educate yourself by reading reviews and descriptions as well as talking to a professional at any time whether it be through email, phone or chat. Each online tire store has dedicated informed employees to answer any questions you may have, just like a local shop would.
YES: If your priority is getting a better deal, then buying online is right for you. In many cases you are buying from the source and have a wider range of products to compare and choose from.
YES: If your priority is selection, the chances of you being satisfied with your purchase are greater online. Many tire manufacturers limit which other brands the tire stores are allowed to carry. Online you can compare and buy any tire from any brand, included tires that may not be available from your local shops.
YES: If your priority is taking your time finding the right tire, then buying tires online is the way to go. There is no salesman, no pressure, no upselling and no people. Shop anytime, you won't have to waist your Saturday driving around comparing prices or rushing to the tire shop on your lunch break.
YES: For those who are purchasing wheels and tires together, buying online is an excellent choice. Most retailers will mount and balance the package for free or minimal cost and they are ready to install when they arrive at your door.
YES: If you are buying tires only, many online retailers will ship directly to the installer of your choice. The store will then notify you when they have arrived and you can simply go get them installed. Or if you like, you can have them shipped directly to your home as well.
NO: Some online retailers may not ship to an installer or you may not have a shop on their list. If so, and you don't have the means or desire to haul the tires to a shop, then buying online may not be right for you.
NO: If for any reason you need tires now, then buying online is sadly out of the question. Although shipping is extremely fast, you will have to wait for them to arrive and have the appointment set to get them installed.
NO: If your priority is the comfort of believing you can get an exact replacement tire in an emergency while out of town, then buying from a big chain tire store may be your choice. If you destroy a tire while traveling, the chances of finding an exact replacement tire in a short amount of time may be better.
HOWEVER: If you bought a tire that is exclusive to the big chain tire store and there is not a franchise in the out of town area, then the chances of finding an exact replacement are almost zero. You would have a better chance of finding a replacement tire if you bought a major brand name tire online.
NO: If your priority is road hazard protection that will cover a damaged tire in the event of an "Out-of-Town Replacement" time sensitive situation, then buying from a big chain tire store may be the right path.
HOWEVER: You can purchase a warranty from some of the online stores. Passenger tires from TireRack.com actually come with a free road hazard warranty. If you have an issue, you just get the work done at a tire shop and they will reimburse you for the tire or flat repair.
NOTE: If you are thinking about a road hazard warranty you should first check prices online for the tires alone. Then compare to the big store price for the same tire with the road hazard warranty. You may want to opt out of the warranty if the price of the warranty is more than the cost of a new tire.