9.03pm BST: So with all the results now in Buhari is the clear winner with 15,424,911 votes to Jonathan's 12,853,063. He secured victory in 21 of Nigeria's 36 states, with Jonathan taking 15 states and the Federal Capital Territory. Buhari was able to secure good results across the country, with the exception of Jonathan's strongholds in the south, winning four of the country's six regions.
The result is a huge victory for Buhari, who was defeated in presidential elections in 2003, 2007 and 2011, but probably an even bigger one for Nigeria, which has seen an incumbent relinquish power in a democratic election for the first time in its history. Preliminary media analysis of the results has also given credit to Jonathan, whose reform of the INEC during the early years of his presidency is thought to have helped in the delivery of a result widely accepted as fair. His timely concession of defeat has also been praised as a positive step towards a smooth transition of power.
8.55pm BST: Reports now emerging that Buhari has won in Borno state, by 473,543 votes to 25,640.
6.00pm BST: With Borno state still to announce its results, Jonathan has conceded defeat. Buhari polled 14,951,368 votes to Jonathan's 12,827,423. Borno state is expected to announce its results in around twenty five minutes.
5.45pm BST: Big win for Jonathan in Delta, but too late to help him - 1,211,405 to Buhari's 48,910
5.35pm BST: Buhari won Sokoto, taking 671,926 votes to Jonathan's 152,199. It is effectively over now.
4.13pm BST: Both candidates secured more than 25% of the vote in Taraba, meaning that a run-off is now impossible.
Jonathan won the state, securing 310,800 votes. Buhari got 261,326. That leaves the current vote count, with three states left to declare, at:
Goodluck Jonathan 11,463,818
Muhammadu Buhari 14,230,542
Jonathan now needs to make up around 2.8 million votes between Borno, Sokoto and Delta states to secure victory.
4.00pm BST: Narrow win for the PDP in Edo state - 286,869 votes to the APC's 208,469.
Goodluck Jonathan 11,153,078
Muhammadu Buhari 13,969,216
The remaining results to be declared are Delta, Taraba, Borno and Sokoto. Buhari needs more than 25% in just one of those to avoid the possibility of a run-off.
3.22pm BST: Yobe declares for Buhari - 446,265 votes to 25,526.
Goodluck Jonathan 10,866,209
Muhammadu Buhari 13,760,747
3.12pm BST: Bauchi state has declared a massive win for Buhari. He polled 931,598 votes, to Jonathan's 86,085.
Goodluck Jonathan 10,840,623
Muhammadu Buhari 13,314,482
That count is after 30 states and the Federal Capital Territory have declared. Buhari has won 18 states to Jonathan's 13. There are six still to announce, including Edo and Delta, which are likely to be big wins for Jonathan. At this point however it seems unlikely that the PDP will be able to pull it back, even with big wins there.
Buhari has polled more than 25% of the vote in 21 states, to Jonathan's 22.
3.00pm BST: Buhari won Benue state, 373,961 votes to 303,737.
Goodluck Jonathan 10,754,538
Muhammadu Buhari 12,382,934
2.38pm BST: Kebbi state has now also declared for Buhari - 567,883 votes to Jonathan's 100,972
Goodluck Jonathan 10,450,801
Muhammadu Buhari 12,008,973
2:27pm BST: Zamfara state has just announced with another win for Buhari - he polled 612,202 to Jonathan's 144,833.
Goodluck Jonathan 10,349,829
Muhammadu Buhari 11,441,090
There are nine states left to announce. Buhari has secured more than 25% of the vote in 18 of the 24 he needs to secure victory without a run-off.
2.14pm BST: Buhari has won Adamawa state - 374,701 votes to Jonathan's 251,664.
Goodluck Jonathan 10,204,996
Muhammadu Buhari 10,828,888
That also brings Buhari one closer to the 24 states in which he needs to secure more than 25% of the vote.
1.36pm BST: Benue and Adamawa expected to announce soon. Edo and Delta among the key states yet to announce.
1.10pm BST: Buhari continues to hold the lead after results have been announced for 25 states and the Federal Capital Territory, having also secured the key state of Lagos with a 22.5% swing from the PDP. Preliminary analysis from various observers suggests that he may have done enough to win, although some of the key areas where incumbent Goodluck Jonathan’s support is concentrated are yet to declare.
Nigeria’s political system dictates that a run-off will be required if the winning candidate fails to secure more than 25% of the vote in two thirds of Nigeria’s 36 states. It now appears highly unlikely that this will be required – Jonathan has secured more than 25% of the vote in 20 states and Buhari in 16, with 11 states still to announce. Jonathan just secured crushing victories in Rivers and Cross River states.
Goodluck Jonathan 9,953,332
Muhammadu Buhari 10,454,187
12.23pm BST: Buhari has won Lagos. It was close – 792,460 votes to 632,327.
After 22 states have announced (out of 37 - 36 plus the Federal Capital Territory) the vote counts stand at -
Goodluck Jonathan 7,954,521
Muhammadu Buhari 9,995,286
Four states have announced today – Buhari won Lagos and Niger. Jonathan crushed Buhari in Ebonyi and Bayelsa.
11.50am BST: Nigeria is in the closing stages of counting ballots in the closest election in the country’s history, and the first in which an incumbent may be forced to relinquish power. Incumbent President Goodluck Jonathan, representing the Peoples Democratic Party, which has dominated the country’s politics since Nigeria’s return to democracy in 1999, is facing a strong challenge from General Muhammadu Buhari, who is representing All Progressives Congress, an umbrella group of opposition parties.
Buhari was the leader overnight after half of the results had been declared, having secured around two million more votes than Jonathan. Buhari, who was military ruler of Nigeria from 1983 to 1985, unsuccessfully contested the country’s presidential elections in 2003, 2007 and 2011. In the closing months of the current campaign the APC attracted public support from a number of major Nigerian power brokers, including retired General Ibrahim Babangida, a former rival of Buhari who deposed him from power in 1985.
It is thought to be highly likely that any declared result will be subject to extensive legal challenges at the state and federal levels, with the possibility remaining that the winner announced today will not accede to the Presidency. There was some indication of the tensions at play this morning, when Peter Godsday Orubebe, the former Minister for the Niger Delta, accused Attahiru Jega, the Chairman of the Independent Nigerian Electoral Commission, of fixing the result in favour of the APC.