Singh bid adieu as Prime Minister of two terms in a televised address where he said the judgement delivered by the people in the elections should be respected by all and wished the incoming government every success.
The 81-year-old economist, credited with playing a key role in ushering in economic reforms in the 1990s, leaves a mixed legacy of achievements and failures during his tenure.
He drove to the Rasthrapati Bhavan from his official residence 7, Race Course Road, to submit the resignation of his Council of Ministers to President Pranab Mukherjee.
Mukherjee accepted the resignation and requested him and his colleagues to continue till the new government is formed.
Earlier this morning, the Cabinet met and recommended dissolution of the Lok Sabha. The Cabinet adopted a resolution lauding the role of Singh.
Looking back, he said India saw many successes and achievements "that we should be proud of" and the country has become far stronger in last one decade. But it still has vast latent development potential.
Singh, the first Sikh Prime Minister, was the surprise choice for the top post when his name was suddenly proposed by Congress President Sonia in 2004 when the party-led coalition UPA was in a position to form government.
"I address you today for the last time as Prime Minister of India. Ten years ago, when I was entrusted with this responsibility, I entered upon it with diligence as my tool, truth as my beacon and a prayer that I might always do the right thing," Singh said in his brief address to the nation.
"Today, as I prepare to lay down office, I am aware that well before the final judgment that we all await from the Almighty, there is judgment in the court of public opinion that all elected officials and governments are required to submit themselves to.
"Fellow citizens, each one of us should respect the judgement that you have delivered. The just concluded elections have deepened the foundations of our democratic polity," Singh said.
Singh, who had achieved the distinction of serving as Prime Minister for the longest consecutive tenure after Jawaharlal Nehru's 17 years in office, chose the occasion to refer to his humble origin as "an underprivileged child of Partition".
"...This great land of ours where I, an underprivileged child of Partition, was empowered enough to rise and occupy high office. It is both a debt that I will never be able to repay and a decoration that I will always wear with pride...
"As I leave office, my abiding memory will be the love and kindness that I have always received from you," he said.
Singh, whose second tenure between 2009 and 2014 saw the government battling various corruption scandals, insisted, "As I have said on many occasions, my life and tenure in public office are an open book. I have always tried to do my best in serving this great nation of ours."
He addeed "In the last ten years, we as a country have seen many successes and achievements that we should be proud of. Today, India is a far stronger country in every respect than it was a decade ago. I give credit for these successes to all of you. However, there is still vast latent development potential in our country and we must collectively work hard to realize it."