Sergey is a municipality in the district of Jura-Nord Vaudois in the canton of Vaud in Switzerland.

[3] Sergey has an area, as of 2009[update], of 1.5 square kilometers (0.58 sq mi).

Of the rest of the land, 0.21 km2 (0.081 sq mi) or 14.4% is settled (buildings or roads).

Argent, a Semi-Bear rampant issuant Sable, langued Gules; 2.

Pally of Six Argent and Azure[6] Sergey has a population (as of December 2020[update]) of 145.

[10] The age distribution, as of 2009[update], in Sergey is; 22 children or 15.8% of the population are between 0 and 9 years old and 17 teenagers or 12.2% are between 10 and 19.

[9] The historical population is given in the following chart:[3][13] The entire hamlet of Sergey is designated as part of the Inventory of Swiss Heritage Sites.

[14] In the 2015 federal election the most popular party was the SVP which received 59.4% of the vote.

[9] There were 51 residents of the municipality who were employed in some capacity, of which females made up 37.3% of the workforce.

[9] From the 2000 census[update], 12 or 11.1% were Roman Catholic, while 73 or 67.6% belonged to the Swiss Reformed Church.

In the Vaud cantonal school system, two years of non-obligatory pre-school are provided by the political districts.

The canton's primary school program requires students to attend for four years.