Saha was unable to don the wicketkeeping gloves on the final day of the first Test in Kanpur due to a stiff neck with KS Bharat taking his place behind the stumps during the drawn Test.
"Saha is fit as of now and he has completely recovered from the neck niggle or spasm that he was suffering from," Kohli told reporters before the Wankhede Stadium test starting Friday.
Kohli himself skipped the three-match Twenty20 series and the opening test against New Zealand to take a rest.
While Kohli's return will be a welcome boost for India's batting, it will also leave them with a selection headache.
In Kohli's absence, Mumbai batter Shreyas Iyer made a dream test debut with a first-innings 105 followed by a crucial 65 in the second in Kanpur.
Calls have grown to drop either Ajinkya Rahane, who led India in Kanpur, or Cheteshwar Pujara - both of whom have been short of runs - to vacate a spot for Kohli and allow Iyer to retain his place.
Unseasonable rain in Mumbai has also meant that both teams have not been able to practise outdoors since Wednesday and the weather conditions could have an impact on the team selection, according to Kohli.
"We will discuss our combination. The change in weather and the change in conditions have to be taken into account," he said, adding that he expected the Wankhede Stadium pitch to have something on offer for batters and bowlers.
"But we also can't assume that the weather will remain the same for the next five days. So we have to have a combination which can adapt to any change."
New Zealand have never won a test series in India, let alone a Test match since the 1988/89 tour.
The top-ranked Black Caps, who beat India in a June contest in Southampton to win the inaugural World Test Championship, have a chance to make history with a win in Mumbai.
"We gained a lot out of our efforts in Kanpur," New Zealand's pace speahead Tim Southee said. "We're just looking forward to a new challenge here in Mumbai."