Zaildar (Hindustani: ज़ैलदार, Punjabi: ذَیلدار) was the position based title of the grand jagirdar (landlord) of the area, who were in charge of a Zail which was an administrative unit of group of villages during the British Indian Empire. Settlement Officer, with the advice of Deputy Commissioner, was responsible for appointing Zaildar from amongst the leading men of the tribe or the area, thus reinforcing his preexisting social authority with the official sanction as the representative of the government. Each Zail was an administrative unit, extending between 40 to 100 villages.: p xxv Each village was headed by the Lambardar who was assisted by the "Safedposh Zamindars" (influential landlords) of the village. Zaildars were the revenue collecting officers and were also responsible for maintaining law&order in his zail. The Lambardar and safedposh assist the Zaildar in his functioning , Zaildar in turn assisted the Deputy Commissioner. The Zaildar was more influential than the Lambardar (village head) because a Zail included several villages in it. Safedposh (white collar gentry), were also appointed to assist Zaildar.
The position was quite important as it extended the influence of the colonial state right into the villages. It also reinforced the already dominant social status of the Zaildar with the official government sanction. The Zaildar exercised tremendous authority among the villagers, many of whom looked to him for patronage and assistance, and he alone possessed the power of threats and blandishment within his Zail.
Zails were established and demarcated by the District collector or (also called Deputy Commissioner) during the land revenue settlement exercise. Settlement officer, with advice from the District collector and by the final approval of the state's Financial Commissioner, appointed a Zaildar to each Zail on either (a) hereditary basis, (b) for one life or (c) a fixed tenure, who were equivalent to the Chaudharis (feudal zamindars) of earlier times and were hand-picked by the higher authorities, who based their decision on issues such as caste or tribe, local influence, extent of landholding, services rendered to the state by him or his family, and personal character and ability.: 97–98  A Zaildar when once appointed should only be removed from office for misconduct or neglect, removal on account of old age or disability caused by an accident is a harsh punishment, in such cases he can continue to operate through a representative.
"The introduction of the zaildari agency into any district must be approved by the local Government [Deputy Commissioner]. Any subsequent increase or decrease in the number of zaildars can be made under the orders of the Financial Commissioner, provided the percentage of the land revenue assigned for their emoluments is not exceeded ... No attempt should be made to fix the limits of zails, but the tribal organization and other important families of the tract should be explained in such detail as is necessary to enable Government to judge whether the agency should be introduced. Any proposals to appoint inamdars [also called safedposh] may be made in the same report. The opinions both of the Settlement Officer and of the Deputy Commissioner should be given. The report should be submitted to Government through the Commissioner and the Financial Commissioner, each of whom should record his views on the proposal made in it."— Punjab Settlement Manual, 1930 (point 578, page 272).
Zaildars were essentially revenue ministers and representatives of the British Empire who enjoyed remuneration for their duties, life grants of either fixed amount or grant equal to one per cent of the revenue of their zails from the assessment of any single village that they chose. Some of the responsibilities of the Zaildar corresponded to the responsibilities that fell under the Deputy Commissioner [such as the revenue collection, mutations, local governance issues, related dispute resolution, etc] and other duties corresponded with the responsibilities that fell under the Settlement officer [such as the revenue settlement, reassessments, preparation of maps, etc]. Some of the notable zaildars were
In addition to these life inams, or grants, there were some Safedposhi grants of a semi-hereditary nature enjoyed by some of the leading agricultural families. They were semi-hereditary because one of the conditions of the grant was that on the death of an incumbent, his successor should, if possible, be a member of the same family. If, however, there was no fit member of the same family, the grant could be awarded to some deserving Zamindar of the same tribe, who was not already in the enjoyment of such a grant.
Post Indian independence in 1947, the system of Zails, Zaildars and Safedposh continued to exist till 1962 by CM P.S Kairon on the demand of his minister and MLAs because Police and Tehsil officers give more weight to their opinion so this created a awkward situation of undermining the elected MLAs over hereditary post of Zaildars.
Zaildar, a book was written by the Kapur Singh Ghuman in 1972. Punjabi movies with Zialdar title include Zaildar (1972), Nikka Zaildar (2016), "Nikka Zaildar 2" (2017). Popular Punjabi singer Geeta Zaildar uses it as his surname.