When choosing a frame, you have two basic options, frame with a mount and frame without a mount.

It really depends on the look you are going for. A classic look requires a mount, whereas if you like a contemporary look, go for a thin frame profile without a mount.

My prints are available in A4 and A3 which are standard international ‘A’ sizes. I don’t sell frames but I can recommend the following frame websites:

Nielsen Pearl
These are probably the best choice of frame if you want to frame without a mount. They are off-the-shelf frames, so no customisation, which also means you can get them delivered fairly quickly. They come in both the A4 and A3 sizes. They are excellent quality for a reasonable price and look great if you are going for the contemporary look.

You can get Nielsen Pearl frames from the Best4Frames website.

They are very good and offer full customisation of your frame, so you can choose the frame profile type, material, mount colour and so on. They are great if you would like a custom size frame and frames with mounts. You will pay more as they are customised, but the quality is superb.

Another option is to visit your nearest Hobbycraft store. They usually have lots of frame options and mounts, so you can pick and choose what you like. They have standard mounts to fit A size prints.