Santander shares

There is a box on the additional information form. I think it's on the first page.

Hi

It depends on whether its the proceeds of a rights sale, a fraction, or a dividend.

Santander guidance here: http://www.santander.com/csgs/StaticBS?blobcol=urldata&blobheadername1=content-type&blobheadername2=Content-Disposition&blobheadername3=appID&blobheadervalue1=application%2Fpdf&blobheadervalue2=inline%3Bfilename%3D785\806\Scrip+Dividend+Scheme+Informaton+Booklet+August+2015.pdf&blobheadervalue3=santander.wc.CFWCSancomQP01&blobkey=id&blobtable=MungoBlobs&blobwhere=1278712789724&ssbinary=true

In my experience, these are usually capital distributions, so CGT proceeds.

For £5, i'd treat it as a pure gain, and covered by the annual exemption (assuming no other gains).