Depended on denomination and social class
Roman Catholic baptisms are generally within week of birth
Many upper middle class CofE would delay several months (eg G W Dumbell an evangelical) had about 4 month gaps between birth and christening in mid 19th C.
Around 1832/3 the cholera epidemic 'encouraged' many to have their children baptised (and also to join methodists etc).
But Nigels comments should also be noted - those for non-comformist + RC pre 1849 are indexed on Brian Lawson's site; there are some Methodist baptisms but most would appear to be also in parish regs