Under the 1874 Act you had up to three months, and a maximum of twelve months to register the birth. This is what the 1874 Registration Act says about late registration
1874 SECOND SCHEDULE.
Fees to Registrars and "Superintendent Registrars.
Upon the registration of a birth when the child is more than three months old, if it is 'not more than twelve months old, to superintendent registrar two shillings and sixpence, and to the registrar (unless the delay is occasioned by his failure to issue a requisition, or otherwise by his default) two shillings and sixpence, and if it is more than twelve months old, and is registered with the authority of the Registrar General, to superintendent registrar five shillings, and to registrar (unless the delay is occasioned by his failure to issue a requisition or otherwise by his default) five shillings, to be paid by the informant or declarant.
Section 2 of the Act says:
2. Where a birth has, from the default of the parents or other persons required to give information concerning it, not been duly registered, the registrar may, at any time
after the end of forty-two days from such birth, by notice in writing, require any of the persons required by this Act to give information concerning such birth to attend personally at the registrar's office, or at any other place appointed by the registrar within his sub-district, within such time (not less than seven days after the receipt of such notice,, and not more than three months from the date of the birth) as may be specified in such notice, and to give information, to the best of such person's knowledge and belief,
http://www.legislation.gov.uk/ukpga/1874/88/pdfs/ukpga_18740088_en.pdfStan