Close to 500,000 voters transferred from their previous polling stations to new ones during the just-concluded mass registration.
A total of 1.4 million new voters were listed countrywide during the drive.
The Independent Electoral and Boundaries Commission (IEBC) has described the huge number of transfers as “largely suspicious” and announced that a proper analysis on what may have prompted it was under way.
A new voter registration report capturing the final mass listing data, which was released Tuesday, shows that 493,169 old voters transferred to new stations.
IEBC Chairman Issack Hassan, who released the document, expressed suspicion on the mass transfers but indicated that the commission had detected they were “motivated by change of residence”.
“It was noted that 493,169 voters applied for transfers from one station to another; one county assembly ward to another, one constituency to another; or from one county to another. The large number of transfers of already registered voters was witnessed across all counties,” said Mr Hassan in a statement.
He said the shocking low turnout during the mass voter registration required an empirical examination.
The commission also noted that counties near Nairobi seem to register higher than their targets.
“Kajiado County, for example, had a target of 18,092 but ended up registering 27,884,” said Mr Hassan.
A commission official said most of the voter transfers were recorded in Nairobi and movements were largely from Kiambu County, with registration mainly focused in Mathare Constituency.
The anticipated competition for the Nairobi governor seat and other elective positions around the country is believed to have led to the move.
Only 1.4 million out of the targeted four million new voters were listed by the IEBC during the mass voter registration.
With the new drive, the Kenyan voters’ register will now have 15,816,837 names after adding the 1,428,056 new ones.
Kisumu Central tops the listing with 12,970 new voters, followed by Kisauni (11,751), Bondo (11,195), Naivasha (10,575), Thika Town (10,448), Ruiru (10,339), Mathare (10,235) and Kitui South (10,215).
Generally, the Rift Valley region, Deputy President William Ruto’s home turf, appeared to have registered the most voters with 285,303 new ones listed, with Cord leader Raila Odinga’s Nyanza backyard following closely with 260,637 new voters.
The report also shows that Cord co-principal Kalonzo Musyoka’s Eastern region listed 240,565 new voters, while President Uhuru Kenyatta’s central Kenya turf recorded 192,092. In the other regions, western Kenya recorded 164,205 new voters, Nairobi (134,670), Coast (129,157), with north-eastern Kenya listing only 21,428.
Mr Hassan said overall, Nairobi County listed the highest number of new voters.