Putin, who has ruled Russia for almost two decades, recorded his best-ever election performance with 76.66 percent of the vote but appeared to reject the possibility of staying in power indefinitely.
Opposition and independent monitors reported ballot stuffing and other cases of alleged fraud as the Kremlin pushed for a high turnout to give greater legitimacy to Putin's historic fourth term.
But fewer irregularities were reported than in previous years, with an OSCE observer mission saying that although the election was marred by a lack of "genuine competition", it was generally well conducted.
Putin's supporters said Western pressure on the Russian leader, including British allegations of his involvement in a spy poisoning row and an Olympic doping ban, had prompted people to close ranks behind him.
Longest rule since Stalin
But Putin, who is already Russia's longest-serving leader since Joseph Stalin and is now set to rule until at least 2024, ruled out any question of remaining president for life.
"What, am I going to sit here until I am 100 years old? No," he told reporters late on Sunday when asked if he would run again in 2030.
The Russian strongman ran against seven candidates, but his most vocal opponent Alexei Navalny was barred from the ballot for legal reasons, and the final outcome was never in doubt.
"I see in this (result) the confidence and hope of our people," a beaming Putin told supporters who had gathered in a square next to the Kremlin on Sunday.
'Thanks to Britain'
Putin's campaign spokesman Andrei Kondrashov said that turnout, which was above 67 percent, was 8 to 10 percentage points higher than expected, saying it was "thanks to Britain."
"Several foreign leaders -- I won't say their names -- made their contribution," said Central Election Commission head Ella Pamfilova.
"Our people always unite in the trying hour."
In Crimea, which was annexed from Ukraine exactly four years ago on Sunday, Putin won more than 92 percent of the vote.
Most of the voters AFP spoke to said they had backed Putin despite Russia's problems of poverty and poor healthcare, praising his foreign policies.
Moscow faces increasing global isolation over its interventions in Ukraine and in Syria, and a fresh round of US sanctions over alleged Russian election meddling in 2016.
In the run up to the vote, a new crisis broke out with the West as Britain accused Russia of poisoning former double agent Sergei Skripal and his daughter, who were exposed to a Soviet-designed nerve agent on British soil a fortnight ago.
The Russian soul as guitar
Authorities used both the carrot and the stick to boost engagement in the polls.
Selfie competitions, giveaways, food festivals and children's entertainers were laid on at polling stations to entice voters.
But employees at state and private companies, as well as students, said they had come under other pressure to vote.
Analysts said Putin used tensions with the West to rally support and suggested that armed with a strong new mandate, he could push through further punitive measures against dissenters.
"He wants to show that there is a little bit of Putin in every Russian, that he plays the Russian soul like a guitar," said political analyst Konstantin Kalachev.
A grim mood
The Organisation for Security and Cooperation in Europe, which observed the polls, said the election was conducted "in an orderly manner" but criticised irregularities related to vote secrecy and insufficient transparency in counting ballots.
"Most candidates publicly expressed their certainty that the incumbent president would prevail in the election," it said.
Navalny said his team planned to stage protests but released few details.
He had urged supporters to boycott the "fake" vote and sent out more than 33,000 observers to see how official turnout figures differed from those of monitors.
Navalny's movement and the non-governmental election monitor Golos reported ballot stuffing, repeat voting and Putin supporters being bussed into polling stations en masse.
But the electoral commission dismissed most concerns, saying there were no serious violations.
Among liberal Russians the mood was grim.
"Have you been thinking about emigrating for a long time? This really is the ideal moment," remarked Stanislav Kucher, a journalist for Kommersant FM radio.
Putin polled well ahead of his nearest rival Pavel Grudinin, the Communist Party candidate, who described the elections as "dishonest".
With 99.84 percent of ballots counted, Grudinin had secured 11.8 percent.
Ultra-nationalist Vladimir Zhirinovsky took 5.66 percent, former reality TV presenter Ksenia Sobchak was on 1.67 percent, while veteran liberal politician Grigory Yavlinsky received just over one percent of the vote.
Western leaders were slow to publicly congratulate Putin.
German Chancellor Angela Merkel's spokesman Steffen Seibert told reporters Merkel would congratulate Putin but would also broach "challenges" in their relations.
German Foreign Minister Heiko Maas earlier said Russia would remain a "difficult partner."
Japanese Prime Minister Shinzo called Putin to congratulate him on his victory as did Chinese President Xi Jinping, who has just gained a path to indefinite rule.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)