Hi.
I just installed Avast on my PC, but have had it on my phone for nearly a year. Am I able to use the same account that I’m paying for on the phone for my 'puter?
Only if you have a multiple device license, one license is only for one device.
More than likely not. Unless, as CraigB mentioned, you have a Multi-Device subscription. For the pro version of Avast Mobile, the subscription is $11.99 USD per year and the lowest Windows OS version subscription package is $59.99 USD per year.
Just that alone tells me there’s no way it would apply to PC unless the devs overlooked that.
I would say the $59.99/year option is actually worth the cash. Real-time and online protection is a must for Windows PCs with how often you can and will run into malware/attacks. No matter how careful you are online, it can and will happen. I learned that the hard way, recently.
However, if you feel comfortable with the free version of Avast for PC, stick with that. Avast is one of the best free security options for PC. From my experience, most other free anti-viruses are a file scan tool with subpar definitions.
Hope this helps.
@ Insomnimatic
The greatest competition the Avast Paid versions have is from Avast Free 
Real time and online protection are core elements in all versions, there are other functions that are available in the paid versions. A lot would depend on the users needs/requirements and some of these features I have a hard time thinking why are they in an antivirus security program
I have been using avast free for over 14 years and no infections.
Agreed and I’ve been an Avast user since around 2008. I’ve tried others but always came back to Avast. I would say it’s the only antivirus that I truly feel is trustworthy.
I had been virus free for many years but I ran into a “mostly undetectable” (mud) memory injected virus, recently. The programmers of this one are consistently trying to make it “Fully Undetectable” (fud). I’ve been keeping tabs on it through Virustotal, though and it recently went from 4 engines detecting to 3. So currently battling it by manually trying to remove its core files.
Lesson learned: You can’t always rely on one failsafe 