Better to wait until you can replace ALL the tile. Any attempt to "match" what you have will fail. Get referrals for a Pro installer from high-end tile shops, pay for an on-site consult. Once you know the cost of install (depends on size of tile and pattern of lay) you'll have a better idea of how much to spend on the tile itself. Be sure to include the cost of removing the old, the dumpster, and any grinding of the surface that may be needed.

If you really want to replace just part of the tile, then I'd try to match it as closely as possible. (Doing all new tile in a simpler color/pattern would be ideal, but I understand $$$ is a concern.)

Old Tile + New tile + Old carpet is going to be an expensive "oopsa" that you are probably not going to like. If you have 10 - 20 boxes of the old tile...go for it. Replace the carpet with the EXTRA tile from the original install. Get everything cleaned up (the current grout needs a good going over) and you are ready for life in your home with TWO types of flooring.

In your single shot, I can see a bedroom doorway only 4-5 feet away from the tile. That means you will have THREE different floors that are visible from a single vantage point. And that is never a good idea. There are dozens and dozens of Houzzers who have inherited/purchased houses with 5-7 different floors from the past owners. These owners where trying, like you are, to save a couple of dollars by replacing their floors "one spot" at a time. And that's how they ended up with 7 different floors in their home.

So, the general consensus is: Replace ALL the tile AND the hallway carpet with the SAME floor. Feel free to leave the bedrooms in carpet. That's fine. There are MANY people who do this. Not a problem. Fully acceptable as a flooring option.

But please do not add new tile to old tile if they abut each other. It is a massive design faux pas. And if you plan on selling in the next 5-15 years, you will need redo whatever you do today because many home buyers do not want to deal with other people's short cuts. If they do accept it, it will be at a discount.

And to be clear, the carpet in the hallways is what is keeping the noise OUT of the bedrooms. Carpets absorb sound. Tiles create MORE sound. If you have tile in the hallways you will find the noise intrusion into the bedrooms will be significant.

If you must have new hallway flooring but cannot afford to retile EVERYTHING, then please replace the carpet with carpet. Carpet is some of the cheapest product on the market that we have. Installation is cheap and quick. That way you can afford to replace hallway carpet AND bedrooms at the same time...for roughly the same price as tiling the hallway. Go ahead and get a quote for carpet in those areas...I bet you will find the cost of material + installation is going to be roughly the same as tiling the hallway.

Their is tile that looks like wood, so you could get a sample and see how that looks. I would redo all or wait until I could. Keep your flooring uniform in all open area as much as Possible

Thanks for all of the advice. We were worried about there being so many different floors in a small space anyway. To replace both all of the tile and the carpet would be more than we can do right now, so I think we are just going with replacing the carpet in both the hallways and bedrooms (where all of the carpet is now). SJ McCarthy didn't think about the noise issue with tile in the hallway. We were looking at wear and tear in a high traffic area and not sound issues. Thanks again - think that helped us make up our minds as to what we want to do. Now on the search for good carpet that we like.