In the 2001 UK census the population of the parish was recorded as 2,918 in 1,203 households.
Heighington chapel, a former church, is dedicated to St Thomas. The building is of 12th-century origin, is Grade II listed, and was restored in 1619 as a chapel by Thomas Garratt, a 'fen-adventurer' of the fen drainage scheme. Garratt gave lands for the support of the teaching of grammar and Latin and the reading of divine service within the chapel. This teaching took place until 1864-65, after which a new attached school house was built by Michael Drury, the older structure reserved for Church of England worship.
In 1885 Kelly's Directory of Lincolnshire noted the presence of Wesleyan and Wesleyan Reform chapels; a Grade II listed Methodist chapel still exists. According to Kelly's the parish of Washingborough, which at that time included Heighington, had an 1881 population of 747, was of 2,147 acres (9 km2), and had agricultural production of chiefly wheat, oats and barley.
Lincolnshire is very low-lying and land had to be drained for agriculture to be successful. The larger drainage channels, many of which are parallel to each other, became boundaries between parishes. Many parishes are long and thin for this reason.
There is much fenland in Lincolnshire, particularly in the Boston and Horncastle areas. Fenlands tended to be extraparochial before the mid 1850s, and although many sections were identified with names and given the title "civil parish", little information has been found about them. Many appear to be abolished in 1906, but the parish which adopts them is not given in A Vision of Britain through Time. Note the WR category Lincolnshire Fenland Settlements which is an attempt to organize them into one list.
From 1889 until 1974 Lincolnshire was divided into three administrative counties: Parts of Holland, Parts of Kesteven and Parts of Lindsey. These formal names do not fit with modern grammatical usage, but that is what they were, nonetheless. In 1974 the northern section of Lindsey, along with the East Riding of Yorkshire, became the short-lived county of Humberside. In 1996 Humberside was abolished and the area previously in Lincolnshire was made into the two "unitary authorities" of North Lincolnshire and North East Lincolnshire. The remainder of Lincolnshire was divided into "non-metropolitan districts" or "district municipalities" in 1974. Towns, villages and parishes are all listed under Lincolnshire, but the present-day districts are also given so that places in this large county can more easily be located and linked to their wider neighbourhoods. See the WR placepage Lincolnshire, England and the smaller divisions for further explanation.