Section 13 of the Finance (Local Property Tax) Act 2012 (as amended) provides that the owner of a relevant residential property on the 'liability date' is liable to pay the LPT charge for that year. The 'liability date' is always 1 November in the preceding year, for example 1 November 2016 is the 'liability date' for 2017. The only exception in this regard was the 2013 'half year' where the 'liability date' was 1 May 2013.
In circumstances where a relevant residential property is sold after the 'liability date', the vendor remains liable to pay the tax for the following year. This remains the case even if the sale is completed before the start of the calendar year. The intended usage of the property by the new owners has no bearing on its LPT status until the next 'liability date', for example 1 November 2017 in respect of the 2018 tax year.
Revenue has confirmed that the property in question was sold after 1 November 2016 and as a consequence the vendor is correctly liable to pay LPT for 2017. The purchaser is not liable until 2018. Any agreements between the vendor and the purchaser to either 'share' the 2017 liability or to refund the tax (to the vendor) are outside the legislation as set down and have no statutory basis.