From 1942 to 1996, 172 acres (0.7 km2) or more than half the reserve's area was leased by the band to the Municipality of Surrey for recreational "parkland" purposes.

[4] In 2006, the Semihamoo reserve was listed by Indian and Northern Affairs Canada as a high-priority community for drinking-water improvements.

[5] In 2014, the First Nation criticized the federal government's new requirements for annual public transparency about the band's expenditures.

[6] In August 2015, shortly after the start of the federal election campaign, the Semiahmoo First Nation's financial report received national attention due to the $267,309 tax-free remuneration in 2013/14 to Chief Willard Cook which may have represented the highest compensation to a politician in Canada.

[7] A June 2003 report for the Greater Vancouver Regional District indicated that the Semiahmoo First Nation is not affiliated with any tribal council and is not involved in treaty negotiations.

Members of the Sencot'en Alliance also indicate that they are signatories to the Douglas Treaties, taken with the British Crown from 1850 to 1854, and are not involved with the current B.C.

[10] The First Nation sponsors a powwow organized by students at Earl Marriott Secondary School in Surrey.

In 2010, the Semiahmoo First Nation erected a 6 foot high fence that extends east from the reservation and follows the length of their land to prohibit access by non-band members.

The Semiahmoo First Nation uses an Apology Ceremony to deal with minor offences committed within the community.