Execution-only broker Interactive Investor is offering investors up to £240 in cash and trading credit if they switch £3,000 or more to the platform by the end of February.
New clients who make the switch before 28 February are eligible for £120 in trading credit in addition to £10 per line of investment transferred, up to a maximum of £120.
Existing customers who transfer a minimum of £3,000 will receive £120 in credit, which is added to the account in four, quarterly instalments.
Interactive Investor chief executive Adam Seale said: "With the effects of RDR [Retail Distribution Review] legislation still rippling through the investment industry, a number of platforms are introducing new charges, and/or increasing existing fees for their clients as they struggle to replace the revenues they previously generated through opaque charging structures.
"For investors whose existing provider has changed their fees, the question is not just whether their existing service will now be more or less expensive than before, but whether it continues to offer value for money."
Alliance Trust Savings (ATS) similarly announced last week that it would offer £150 cash back to customers who open a new account and transfer existing investments to an ATS ISA or Individual Dealing Account by 11 April.
ATS managing director Patrick Mill said the offer may be attractive as "many savers will only now realise the costs they have been paying elsewhere for their investments".
Last week, rival Hargreaves Lansdown announced its 'unbundled' pricing structure. This included that, as from 1 March, it will charge an annual fee of 0.45% for investments of up to £250,000 on its Vantage service.
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