Business is split over Brexit. The Confederation of British Industry (CBI) says 80% of its members want to remain in the EU. A new survey this week showed 46.1% of SMEs would prefer to leave it.

That SME survey, it should be noted, was carried out by five chartered accountancy firms and asked 400 businesses in Essex, Lincolnshire, London, Middlesex, Buckinghamshire, Yorkshire, and Lancashire. The CBI poll also sampled 773 businesses. Any sample under 1,000 does not meet the standard required by statisticians to be statistically relevant.

A British Chambers of Commerce survey of more than 2,000 senior business people taken in February showed a 60% to 30% result in favour of Remain. The survey showed that among micro businesses the Remain side polled 53.9% with Leave at 33.5%, with small businesses employing under 10 people polling at 59.7% for Remain and 31.4% for Leave. Large business voted 74.7% for Remain to 19.8% for Leave.

Few pollsters would call the result of the vote confidently right now, and few economists would be rash enough to claim they can accurately predict what would happen if Britain leaves the EU.

One thing we can all see for ourselves is the way the debate has impacted on the currency market – substantial falls in the value of the pound amid fears the Leave arguments had gained ground, a huge rally as the pendulum appeared to swing back to the Remain campaign over the weekend.

For small businesses, who are split on whether to stay or go, that would be the major short-term impact of a decision to leave in Thursday’s referendum. The value of the pound is highly likely to fall sharply again.

So what would that mean for small business?

For those who import raw materials or goods, a fall in the value of the pound means the value of their money being severely reduced – putting pressure on their own financial position as they effectively pay more for the same goods.

For those who export, that might make their products more competitive to those in other countries. What we don’t know is whether a vote to leave would later hit small businesses in the pocket through import charges and taxes being imposed in EU countries on British goods.

The other major impact would be on Britain’s imports and debt abroad, both of which would become much more expensive to us overnight. The price of imports like gas and petrol will affect the price of almost every good or service in the UK. If we have to spend more of our currency to get them, that’s bound to be reflected in prices paid by consumers. Keeping up our debt payments could also have a ripple effect throughout the whole economy.

If we vote to leave, how would we trade?

If a Norway-style arrangement is made between Britain and the EU – and that’s something which cannot be guaranteed – it would still involve the UK allowing freedom of movement and paying hundreds of millions of pounds every year to be part of the single market.

That would allow British SMEs to take advantage of the market almost as they do now.

However, some Leave campaigners are now suggesting Britain should turn its back on the single market and negotiate individual trade deals using World Trade Organisation rules. Whether that would mean British firms could export in the same way, or if they would face new taxes from countries in the EU, remains to be seen. The IMF has warned that situation would raise trade barriers.

One impact of a vote to leave without a Norway-style arrangement might be tighter immigration controls for EU citizens. Some businesses looking for trained staff from the EU might find this has a negative impact on them, and that they face staff shortages. For those in the private healthcare sector looking for trained nurses, for example, the search might have to be made worldwide. Would that add to a business’ costs? It’s difficult to predict. The impact on existing staff who are EU citizens is also uncertain.

Would the UK go back into recession if we leave the EU?

There have been claims on both sides on this issue. Going back to the British Chambers of Commerce survey, 39% of the 2,000 questioned said they believed a vote to leave would have a negative impact on their business’ growth plans. 36% said they believed it would have no impact, and 17% said they believed it would have a positive impact. (You can read more on that survey here.)

Just a few days ago, the IMF said Britain could miss out on between 1.4% and 5.6% in growth by 2019 if we leave the EU.

It said the impact of a Brexit would be “negative and substantial”. Pro-Brexit economists claim the figures are flawed.

Brexit campaigners say funds saved from not being in the EU could be used to bolster public services. If we do go back into recession, though, tax receipts will fall and there will be further pressure on public services.

Those who are looking for simple answers and certainties in the economics of the situation won’t find them.  There are still so many questions which cannot be answered by what we know right now. If there are negative impacts of a Leave vote, how long would they last? Would the long-term outlook be positive?

The only certainty is this: On Friday, months of uncertainty about how the country will vote will finally be over.