Customers of New Millennium Technologies (NMT) are defecting to Sirius Financial Systems and insurE.com, after the software company was placed into administration last week.
Sirius announced it had signed its first agreement with an NMT customer this week.
The commercial lines broker customer said: "We look forward to taking delivery of our new system later this month and have taken prompt action to ensure our business is not jeopardised by NMT's demise."
Sirius systems division managing director Kevin Child said that Sirius was currently in negotiation with "several other clients of theirs, all of whom are equally keen to ensure that the impact on their businesses is minimal".
InsurE.com announced it had received a "dramatic surge" in inquiries from brokers.
Chief operating officer Chris Newman said "the majority of NMT users" had shown an interest in the insure-E.office system.
NMT managing director Barry Singh said: "There are things that have happened in the last week, but nothing that I want to talk about."