Calculating cost base for sale of foreign shares

Hello, I have some shares in an Australian listed company that I'm looking to sell, and have a few questions about reporting capital gains. 1. Do I calculate cost base on a first-in-first-out basis for shares? I've had a dividend reinvestment plan for a while so have acquired shares over a number of years. E.g. If I have 750 shares now and sell 400, do I calculate the cost base on the first 400 shares I acquired? 2. Do I calculate the value of shares (when acquired and sold) on the close price on the relevant dates, or the adjusted close price? 3. In my tax return when declaring capital gains, do I use the exchange rate (AUD > GBP) on the date of sale or the official HMRC monthly exchange rate? 4. According to the UK/Australia double taxation treaty article 13.5, as long as I am now a resident of the UK and no longer a resident of Australia, I can declare capital gains for the sale of Australian shares and pay tax in the UK only, and I don't need to declare capital gains from sale of shares in Australia... am I interpreting that correctly? Thanks!

Hi
Have a look at Shares and Capital Gains Tax (Self Assessment helpsheet HS284) regarding pooling shares of the same type together under a section 104 holding.
For capital gains purposes there is no fixed rate you must use.
Under the terms of Self Assessment, we do not provide an official exchange rate and the onus is on the individual to use a just and reasonable exchange rate for each acquisition and disposal.
HMRC does have a set of exchange rates for other purposes, that you can choose or you could use the closing value of the shares at acquisition and disposal.
The choice is yours.
The exchange rates provided by HMRC, can be found at Exchange rates from HMRC in CSV and XML format
and for older exchange rates at HM Revenue & Customs: Exchange rates
If you are UK resident at the time of the disposal of the share, then under the DTA, they will be taxable in the UK.
Thank you

Hello, following on from the question above. Based on the section 104 method of calculating the cost base of multiple acquisitions, it would appear that one should use the average cost of the shares purchased. Do we need to convert the gain as computed in the foreign currency back to sterling based on the prevailing exchange rate on the date of disposal or do we convert each component of the calculation separately, i.e. the proceeds converted based on exchange rate on the date of disposal and acquisition costs are converted based on exchange rate on the various dates of acquisition, bearing in mind that the shares disposed of were acquired on multiple dates, in which case are we applying a FIFO method in identifying the shares being disposed of?

Hi,
The Self Assessment tax return requires that all values entered are in pounds sterling. Under the terms of Self Assessment, we do not provide an official exchange rate and the onus is on the individual to use a just and reasonable exchange rate for each acquisition and disposal, which includes S104 holdings. For your convenience, there are exchange rates here:
Exchange rates from HMRC in CSV and XML format
and for older rates here:
Foreign exchange rates and spot rates: 1 January 1989 to 31 March 2009
You are free to use any of the supplied rates or one of your own choosing. 
Thank you.