Hello and welcome to the site. Thank you for your question.
Figures that go in the reserves section of the balance sheet are
AC70 - called up share capital
This should be the same as what you had at last year's balance sheet. You would only change the figure if you were to issue more shares or the structure of your share capital changed.
AC74 - profit and loss account
This is cumulative retained earnings and the figure should agree with AC187 (retained profit within Statutory Account Notes)
as an example - say last year was your first year of trading and you finished the year with a profit of £1,000 and there were no dividends paid. This figure would appear in boxes AC41, AC75 and AC216.
This year you make a profit of £2,000 and there are no dividends paid.
Your entries would be
AC40 = 2,000
AC74 (2,000+1,000) = 3,000
AC184 = 1,000
AC185 = 2,000
AC187 = 3,000
I hope this is helpful and answers your question.
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