Kotelawala was born on 4 April 1895 to John Kotelawala Snr, a police inspector, who later turned businessman and Alice Elisabeth Kotalawala (née Attygalle), daughter of Mudaliyar Don Charles Gemoris Attygalle, a wealthy land and mine owner.
He had a younger brother Justin Kotalawela and a sister Freda, who later married C. V. S. Corea.

The Kotelawalas lived in considerable comfort owing to the considerable land and mine holdings of his grandfather Mudaliyar Attygalle, which his father managed following the death of his grandfather.
After he was forced out of the management of the Attygalle estates by the family, Kotelawala Snr started his own business ventures including the Ceylon-Japan Trading Company.
In 1907, he was arrested and found guilty of conspiring to murder his brother-in-law, Francis Attygalle.
While the murder trail was underway, Kotelawala Snr committed suicide by poisioning himself.

Kotelawala was eleven years old when his father died and with this the family fortunes declined, after much funds were spent in the legal defense of his father.
Alice Kotelawala who had converted to Christianity, slowly built up the family wealth through careful management of their remaining land holdings and the share of the Kahatagaha graphite mine, which she received from her younger sister Ellen and brother-in-law, Fredrick Richard Senanayake.
She was reputed for her social work and was later awarded a MBE in the 1939 Birthday Honours and a CBE in the 1951 Birthday Honours.

Young Kotelawala attended Royal College, Colombo, representing the school in cricket, tennis, boxing and football.
He played in the Royal–Thomian.
He had to leave owing to involvements in the riots in 1915, embarking on a tour of Europe, with World War I raging.
He remained in Europe for five years, spending most of that time in England and France, attended Christ's College, Cambridge to study agriculture.
Kotelawala was known as an aggressive and outspoken man who loved sports, horseback riding and cricket and, particularly as a young man, got into physical fights when he was insulted.
He was fluent in Sinhala, English and French.
After returning to Ceylon, he became a planter, running his family plantation estates and mines, which included the Kahatagaha Graphite Mine in Dodangaslanda.
He served as a Justice of the Peace.
Kotelawala was born on 4 April 1895 to John Kotelawala Snr, a police inspector, who later turned businessman and Alice Elisabeth Kotalawala (née Attygalle), daughter of Mudaliyar Don Charles Gemoris Attygalle, a wealthy land and mine owner. He had a younger brother Justin Kotalawela and a sister Freda, who later married C. V. S. Corea.
The Kotelawalas lived in considerable comfort owing to the considerable land and mine holdings of his grandfather Mudaliyar Attygalle, which his father managed following the death of his grandfather. After he was forced out of the management of the Attygalle estates by the family, Kotelawala Snr started his own business ventures including the Ceylon-Japan Trading Company. In 1907, he was arrested and found guilty of conspiring to murder his brother-in-law, Francis Attygalle. While the murder trail was underway, Kotelawala Snr committed suicide by poisioning himself.
Kotelawala was eleven years old when his father died and with this the family fortunes declined, after much funds were spent in the legal defense of his father. Alice Kotelawala who had converted to Christianity, slowly built up the family wealth through careful management of their remaining land holdings and the share of the Kahatagaha graphite mine, which she received from her younger sister Ellen and brother-in-law, Fredrick Richard Senanayake. She was reputed for her social work and was later awarded a MBE in the 1939 Birthday Honours and a CBE in the 1951 Birthday Honours.
Young Kotelawala attended Royal College, Colombo, representing the school in cricket, tennis, boxing and football. He played in the Royal–Thomian. He had to leave owing to involvements in the riots in 1915, embarking on a tour of Europe, with World War I raging. He remained in Europe for five years, spending most of that time in England and France, attended Christ's College, Cambridge to study agriculture. Kotelawala was known as an aggressive and outspoken man who loved sports, horseback riding and cricket and, particularly as a young man, got into physical fights when he was insulted. He was fluent in Sinhala, English and French. After returning to Ceylon, he became a planter, running his family plantation estates and mines, which included the Kahatagaha Graphite Mine in Dodangaslanda. He served as a Justice of the Peace.
John Kotelawala