Should I contact the Revenue myself or wait for them to contact me?

I have had a BTL property for nearly 2 years. I am in PAYE employment so rarely get a tax return to complete. Can I wait till I get a tax return to complete before declaring it or would that be counter productive?

Arthur Says

If a taxpayer receives any taxable income in a tax year of which the Revenue is unaware, then they have a legal duty to inform the Revenue about this by 5 October.

So, for example, if any income was received between 6 April 2004 and 5 April 2005, then the individual must inform the Revenue by 5 October 2005. If the amount was £15,000 or less, then a 'short' tax return will be all that they need to complete.