This lack of planning is revealed in a survey published today by the Quoted Companies Alliance (QCA) and accountancy firm BDO, which believe the report suggests small and mid-cap companies are taking a "short-term and narrow view" towards business planning.
The latest QCA/BDO small and mid-cap sentiment index also shows that 48 per cent of companies think that a rise in base rates from their record low of 0.5 per cent, where they have been since March, 2009, would have no impact on their businesses.
The survey found that 77 per cent of companies anticipate a rise in base rates by March next year.
Neil McGill, director of BDO, said: "Indications point to the Bank of England raising interest rates in the near future.
"However, the lack of planning among companies suggests that they are only considering the primary impact this would have on their own working capital.
"Despite the likelihood of small incremental rate changes, companies cannot be complacent. The compound impact will be far greater. It is imperative companies consider the secondary and tertiary effect a rise in rates would have on their customers, suppliers and the health of their markets."
The report shows that, while 55 per cent of small and mid-cap companies have not run any scenario testing for a rise in interest rates, around 22 per cent do intend to undertake some form of "scenario testing" in future.
QCA chief executive Tim Ward said: "Low interest rates have supported an impressive run of recent economic growth... Companies now need to take a longer-term, realistic approach to planning for interest rate rises. They also need to consider other external factors, such as exchange rates and energy costs."