my stored contacts that have the country code prepended doNOT get matched to existing calling contacts due to travelling frequently I tend to store every contact in my phones (current and the ones I had in the past) along with the country code in which it resides. so I can still call them when I'm away.

The problem is that with my latest android phone a Samsung GT-S6310 with android OS 4.1.2 when someone calls me from the same country I'm in right now, the number that shows up on my screen does not have the country code prepended. As a result, the number is not matched to one of my existing contacts and I see just a 10digit number calling instead X calling.

Now this is not the 1st android phone I have owned and I know this was not a problem with the old one. Is there any way to avert that?
If you want a quick answer (two in reality) here is what I would do: 

1) Go to Settings > Accounts > remove the Google account > add it back. 
   I tried it once and it worked... 
2) Go to Gmail on a desktop > Go to Settings (the gear icon in the top right) > Under General, go to 'Phone Numbers' and select your default country code from the dropdown list. 
   This way your device should automatically recognize incoming call from your country...  

I'm not sure if one of these is the solution to your issue, but I know that many people solved the same issue using them. Just try and tell me if they work. If not, we'll look for another solution ;)