Where to buy cardboard boxes?

Either Amazon, or get shops to save them for you.

I was searching for exactly the same thing recently, I need to buy some boxes and bubble-wrap soon. There were a few companies I bookmarked, this one is in Fgura, so probably closest to your area.

http://www.transpakmalta.com/packing.aspx

If you search for Overseas Removals on Yellow Pages, you'll find a few more.

https://www.yellow.com.mt/headings/Overseas-Removals

Thnx guys, i have asked a shop near me and they told me to come tuesdays! i hope i'll find the size i need.
I will definitely check the shop in fgura as well, because i'd rather get new boxes.

I managed to get about 200, all different sizes, from various shops. Supermarkets are good because they leave them out. TV and Computer shops have really good quality boxes, to protect fragile screens, so they were great too. When we moved house (within Malta), I just asked all the local shops to save boxes for me, and I picked up a few every time I went to the supermarket. It was very easy! (And free )

Might be a bit late as the lady asked the question nearly 18 months ago!

Ray

i know this is a very old post but it comes up in google and so i wanted to add the answers i have found.
HMS group movers sell boxes for 3.50 each size  - 60x30x40 cm
Dexter moves offers free boxes if you use their services. dont know the size though.

What sized cardboard boxes are you looking for?