As questions arise about future access to tax privileges and products currently available UK-wide, a survey by Martin Aitken Financial Services found two thirds of 170 clients expressing worries over their finances in a future Scottish state.
The Glasgow-based tax and advisory firm said nearly 65 per cent of clients and contacts interviewed said worries over higher business and personal taxes were "keeping them awake at night" in the run-up to the referendum. More than 70 per cent of clients polled in the survey said they were concerned about their personal wealth in an independent Scotland.
The SNP has long pledged to use devolved tax powers, granted by the Treasury regardless of the referendum's outcome, to suit the nation's needs. The Yes campaign says: "For the first time ever there will be a guarantee that taxes will be set by a government that has the support of the people of Scotland."
Alasdair MacDougall, director of Martin Aitken, commented: "People, businesses and markets can deal with bad news but what they do not like is uncertainty.
"A number of our clients live and work in England as well as Scotland, and many have put a moratorium on any business north of the Border at present. For instance, investment clients in London who may have previously had commercial-property interests in Scotland are buying nothing here at the moment."
The snapshot comes as experts disagree about whether Scots could pick and choose jurisdictions to house their savings nest eggs. Fund supermarket Hargreaves Lansdown has previously argued that savers could exploit different tax environments in the UK and Scotland by weighing up which one has "preferential investment terms" compared to the other.
The Scottish government has said it would allow cross-border financial transactions to take place. However, National Savings and Investments, the Treasury-backed provider of the popular Premium Bonds and savings certificates, has confirmed that Scottish customers would not be able to take out any new products post-independence unless they hold an English bank account.
Even if Scottish customers met that criteria, NS&I could still turn them away; it shut down 2,700 US savings accounts this summer after an American tax clampdown made administration costs "disproportionate". The independence White Paper said the creation of a Scottish NS&I would not be an "early priority" in a low-interest-rate environment.
Some Scottish savers may not mourn the loss of flimsy returns on NS&I accounts and the low odds of winning the Premium Bond's £1 million jackpot. But all could miss out on the UK's recently-improved Isa allowance of £15,000 in tax years to come, said David Welsh, tax and trust solicitor at Turcan Connell in Edinburgh. "Given that the Isa allowance is designed to shield savings from income tax and capital gains tax, savers could only live in official UK tax territory to benefit."
Jeffrey Mushens, technical director at the Tax Incentivised Savings Association, said: "The government has said it would honour existing tax-free products held by Scots post-independence but only UK residents are eligible for Isas, so would the Scots be treated any differently? EU law does not permit preferential treatment in this way."
Mr Mushens also argued that a Scottish government may have difficulty in identifying those who have taken out Isas with English firms, as HM Revenue and Customs would not hand over "sensitive information" about taxpayers that easily.
He added: "An alternative Scottish HMRC would have to be established if it wishes to support tax-free savings allowances and set up a "Sisa". But it will take a long time to build the systems - a proposed timeframe of 18 months post-independence is delusional."
English residents in Scotland and cross-border workers could also face a squeeze on their personal tax allowance in the event of independence. The Treasury is consulting on plans, originally proposed in this year's Budget, to restrict the personal allowance - currently £10,000 for all those born after 1948 - for non-UK residents if a significant proportion of their income is derived "overseas".
Ronnie Ludwig, tax expert at Saffrey Champness in Edinburgh, said: "There could also be an impact for expat citizens who have chosen to live abroad, such as retirees. Unless a very high percentage of their income is derived from the UK, they could be caught in the net. They may find themselves having to rearrange their affairs in response to the new measures."
Mr Welsh said: "This is where the issue of tax residency would become complicated. If, for example, your family home is in Berwick but you work in Edinburgh - not an uncommon scenario - then it becomes uncertain as to which tax treatment you would receive.
"The situation is similar to Northern Ireland and the Republic of Ireland, with many living on one side and working on the other. Each of the separate jurisdictions would have to look at residency rules to determine where your main home is and whether you are resident there."