If I'm using wifi on one of my laptops, does it use up my data usage?

Anything you do on the Internet, not matter how small (like loading a web page or chatting on Facebook) or how large (like downloading a movie), that you do connected to your router (via wifi OR via cable) will use up data. I suggest switching to an unlimited broadband package if this is going to be a problem.

Some ISP plans offer facilities to get round monthly limits. The obvious one is those plans that offer unlimited monthly limits. However, in the UK, BT Broadband users can access the Internet through public hotspots offered by the routers of other BT Broadband users. BT claim that there are over 5 million hotspots in the UK alone and a further 6.5 million hotspots around the rest of the world. There is no monthly limit when users are using these public hotspots.

Although my data plan limits me to 40 GB/month on my normal home network (both Ethernet and WiFi), my router provides a second WiFi network that is available to any BT Broadband user who is within range. This public network requires the user to log on to a home page to get access to the Internet. The public network does not use encryption so it is suitable only for publically available information, but many downloads can be made over the public network while the private WiFi network is fully encrypted (mine is WPA2-PSK), and is used for such things as Internet banking. When I want to perform large downloads, I switch my laptop over to using the public hotspot WiFi from my router to bypass the restrictions of the monthly limit. HTTPS access is still secure even over these public hotspots as it carries its own encryption.

There may be other ISPs that have similar facilities. If you do not have access to such WiFi services, then you will have to stay within the restrictions of your Internet plan.

I hope this helps.

It will use data based on the host device. If it's hooked up to your router, it will count against that. If it's hooked up to your phone, then it will use your phone's data. If you are using community wifi, then it's covered through the rent/ HOA fees.

Yes, it is consuming the data on your internet plan, just like your previous laptop.

Yes, anytime you are connected to your internet plan and using it to be online or download something then yes you will be using up the data that is on your plan.

Yes of course.

Unless of course you're connecting to someone else's wifi.

yes it will consume your data.. to load any page it needs internet so..