Family First has been stripped of its charity status.
The Charities Registration Board said in a decision today the reason was "because it does not advance exclusively charitable purposes".
"The board considers that Family First has a purpose to promote its own particular views about marriage and the traditional family that cannot be determined to be for the public benefit in a way previously accepted as charitable," said chairman Roger Holmes Miller.
"Family First has the freedom to continue to communicate its views and influence policy and legislation but the board has found that Family First's pursuit of those activities do not qualify as being for the public benefit in a charitable sense."
In April 2013, the board removed Family First from the Charities Register for the same reason but that decision was appealed in the High Court.
In June 2015 the High Court directed the board to reconsider its decision in light of a 2014 Supreme Court Greenpeace judgment and its own judgment.
This decision represents the board's reconsideration of Family First's eligibility for registration.
Holmes Miller said the board's role was to maintain the integrity of the Charities Register by ensuring that entities on the Charities Register qualify for registration.
"The board can direct charities to be removed from the Charities Register when they do not advance a charitable purpose for the public benefit and it is in the public interest to remove them."
National director of Family First, Bob McCoskrie, said it was filing an appeal to the decision in the High Court at Wellington.
"This is a less-than-satisfactory procedure of trudging back to the same court," he said.
"It seems that the Charities Board are simply hoping for a different judge and a more favourable decision. It is a highly politicised and inconsistent decision by the Board and will have a chilling effect for many not-for-profit charitable groups - both registered, deregistered and wanting to be registered - who advocate for causes, beliefs, and on behalf of their supporters, and often have to engage in advocacy at a political level, not always through choice but through necessity."
McCoskrie, said the decision threatened other charities and their freedom to speak and advocate on behalf of their "supporters in a civil society".
"It appears that certain views of marriage and family are now deemed out-of-bounds by the State. We'll fight that political correctness and muzzling of free speech."