Market Insider

This is the real wild card for oil prices: Survey

Meaningful Saudi oil cut? 95% say no: Survey

Oil supply is the biggest factor weighing on oil prices, and Iran's return to the market appears to be one of the most difficult supply sources to forecast, according to findings of a new CNBC Oil Survey.

Conducted last week, the survey of 22 top analysts and traders shows answers on when Iran is expected to return to the market to be all over the calendar. In the survey, 23 percent expect Iran to return to the market in each of the first or second quarters of 2016; another 27 percent expect it to be in the second half of 2016, and 14 percent see it happening as soon as the fourth quarter of this year. Fourteen percent say they just don't know.

Read MoreCNBC Survey: Oil prices seen below break even for frackers

Iran has said it could increase exports by a million barrels a day, but analysts have been skeptical and see it adding less output. However, Iran also has an estimated 50 million barrels of crude on tankers that could be sent to global markets quickly.