With just under a week of the Guardian and Observer 2018 appeal to go, generous readers have raised more than £750,000 for five charities that helped uncover the Windrush scandal.

The charities provide legal assistance, advice, advocacy – and often welfare support – for migrants and UK citizens facing injustice, homelessness and destitution caused by “hostile environment” immigration policies.

The appeal charities are: Praxis Community Projects; Joint Council for the Welfare of Immigrants (JCWI); Refugee and Migrant Centre Black Country and Birmingham (RMC); the Runnymede Trust; and Law Centres Network.

Sally Daghlian, the chief executive of Praxis, said: “The generous response of Guardian and Observer readers to the appeal is truly heartwarming. It is wonderful to know that so many individuals are prepared to step in and help others, even whilst government policy condemns people to the streets.

“By working together we can make the UK a more hospitable place, where people are able to live in safety, and where what brings us together is greater than what separates us.”

The Guardian’s award-winning coverage of the Windrush scandal focused in many cases on individuals supported directly by our appeal charities. The charities’ work ensured their clients were not unjustly detained or deported, and in some cases meant they received the vital NHS treatment wrongly denied to them.

However, the charities said, despite the government’s acknowledgement of the Windrush problems, the injustices are continuing. They said they anticipated similar problems arising for EU migrants after Brexit, with long-established UK residents struggling to provide documentation to prove they have a right to be in the UK.

Julie Bishop, the director of Law Centres Network, said: “We can all do something to push back against the hostile environment. Law centres use their legal know-how to get justice for people who have been excluded and restore their dignity.

“We are grateful that so many readers are joining the fightback through their generous donations. Together we can bring down this cruel policy.”

The total raised so far includes £45,000 pledged by readers during the appeal telethon in December, and nearly £10,000 raised by Guardian and Observer staff through fundraising events. The appeal remains open until 6 January.