Máxima of the Netherlands and King Willem-Alexander attended the inaugural event of the new Pope's pontificate last weekend. There, the royal couple of the Netherlands confirmed the rumors: Máxima, despite being Catholic, doesn't hold the "privilege of white." The decision granting this right is given by the Pope, and in Queen Máxima's case, it is final: she will never obtain it.
The main reason is that her husband, King Willem-Alexander, is Protestant, so the Netherlands is not considered a completely Catholic monarchy. For this reason, at the inaugural mass, Queen Máxima dressed in strict black, marking the difference with other European queens.

Máxima of the Netherlands and King Willem-Alexander star in a last-minute news
Last weekend, Pope Leo XIV offered his inaugural mass before a large number of international representatives from around the world. Among them were Máxima of the Netherlands and King Willem-Alexander as representatives of the Royal House of the Netherlands.
The visit of Queen Máxima to the Vatican caused many questions among royal observers and lovers of traditional Vatican protocol. It is that she and King Willem-Alexander confirmed with their presence the rumors: Máxima doesn't hold the "privilege of white." Despite professing the Catholic faith for more than two decades, she dressed in strict black.
The reason behind this decision is not coincidental, but it responds to the faith professed by her husband, King Willem-Alexander, of Protestant tendency. The "privilege of white" is reserved only for Catholic queens of royal houses that have had a direct historical connection with the papacy. Since the Dutch Royal House has Protestant roots, Máxima is not among the women authorized to wear white before the Pope.
For this reason, she was one of the few who wore black at Leo XIV's inaugural mass, differentiating herself from other European queens. In this sense, only five queens hold the "privilege of white," and next weekend they made use of it. Among them, Queen Letizia, who also wore a mantilla.
King Willem-Alexander prevents Máxima of the Netherlands from obtaining the "privilege of white."
During Pope Leo XIV's inaugural mass, Queen Máxima of the Netherlands was one of the few who attended dressed in black, following protocol. Although she is a practicing Catholic, she doesn't belong to the royal elite that enjoys the exclusive privilege of wearing white before the pontiff. This shows that this privilege is not religious but dynastic and political in essence.
Máxima of the Netherlands, although born in Argentina and converted to Catholicism, is the wife of a Protestant king, which limits her access to this privilege. Therefore, it is King Willem-Alexander's religious origins that prevent Máxima from obtaining that right.

The House of Orange-Nassau is of Protestant tradition, and therefore its queen consort is not part of the select authorized group. The decision by the Holy See is irrevocable, and the Dutch queen will never be able to wear white before the Pope. Therefore, her black attire, accompanied by a veil, shows respect for Catholic liturgy and Vatican hierarchy.
Currently, only a few women in the world have the right to dress in white in front of the Pope during religious ceremonies in the Vatican. Among them are Queen Sofía and Letizia, both for belonging to the Bourbon dynasty.
Our royal family has kept close ties with the Catholic Church over the centuries, which supports their access to the privilege. Other queens who can also wear white before the Pope are those of Belgium and Luxembourg, all from traditional Catholic houses.
For this reason, although Máxima is personally Catholic and devout, her link with a Protestant monarchy prevents her from availing herself of the right to the white dress.