This is the highest level recorded since the second quarter of 2015, when 35% were more optimistic, and up from the 27% found at the end of last year.
These findings are in stark contrast to those seen just after the referendum, when only 3% were more positive about their future prospects, although Brexit is still seen as the top risk posed to CFOs.
Deloitte chief economist, Ian Stewart, said: “The Brexit shock that hit corporate spirits last June has eased. Optimism among CFOs has hit an 18-month high and uncertainty has fallen from a post-referendum record high to levels last seen in early 2016.
“Brexit still tops the risk list, although at a lower reading than the last two quarters. CFOs believe the Brexit headwinds have eased and see far less damage to their spending plans than earlier expected.
“While most still see Brexit having an adverse effect on the business environment, even here the degree of negativity has fallen.”
The Deloitte survey took place last month and involved 130 CFOs of 91 listed companies, with a combined market capitalisation of £376bn – approximately 15% of the UK quoted equity market.
In addition to more optimism, it was found that risk appetite continues to climb, with 26% of CFOs saying now is a good time to take risk onto their balance sheets, up from 21% in the previous quarter, and 8% after the referendum.
Overall, 60% believe the business environment will be worse when the UK leaves the EU, although this is down from 66% in the previous quarter, while 19% say it will be better, up from 14% at the end of last year.
“It is clear from this survey that the UK corporate sector enters the negotiation phase of Brexit in far better spirits than seemed likely in the months after last year’s referendum vote,” Deloitte chief executive, David Sproul, said.
“Businesses will hope that the UK can secure the best possible deal on trade and market access, but must continue to plan for an exit in 2019, several years of trade negotiations, and a transitional phase to bridge the two.”
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