From December 2017 to April 2019 was he Director of Uždaroji akcinė bendrovė „Jonavos vandenys“.

In May 2024, Sinkevičius was convicted by a court in Kaunas of abuse of office, falsification of documents, and misappropriation in a case involving damages of 1,487 euros to the Jonava District Municipality and the use of public funds to pay for his wife's phone bills and other personal expenses.

He was sentenced to pay a 12,500 euro-fine and was also banned from holding public office for three years.

His mother Ligita is a chief specialist at the Environmental Protection Agency under the Ministry of Environment.

His wife is Aistė Sinkevičienė (* 1989, Plūkaitė), an interior designer from Kaunas.