Hi, I am quite confused about what happens to the revaluation reserve after an asset is sold.
Assuming the asset's original cost was $100, and afterwards get revalued to $150.
Accounting entry - Dr Asset $50, Cr Revaluation Reserve $50

When the company sells the asset for $180, the treament is to:
Dr Cash $180, Cr Asset $150, with a Gain on disposal of $30 shown in the P&L.
Then what happens to the Revaluation Reserve?

It can either be left in the revaluation reserve, or transferred to retained earnings.

If transferred to retained earnings, it must directly transfer to retained earnings i.e. - it must not go through the profit & loss account.