Your child may be able to get free school meals if you get any of the following:

Income Support
income-based Jobseeker’s Allowance
income-related Employment and Support Allowance
support under Part VI of the Immigration and Asylum Act 1999
the guaranteed element of Pension Credit
Child Tax Credit (provided you’re not also entitled to Working Tax Credit and have an annual gross income of no more than £16,190)
Working Tax Credit run-on - paid for 4 weeks after you stop qualifying for Working Tax Credit
Universal Credit - if you apply on or after 1 April 2018 your household income must be less than £7,400 a year (after tax and not including any benefits you get)

Children who get paid these benefits directly, instead of through a parent or guardian, can also get free school meals.

Your child may also get free school meals if you get any of these benefits and your child is both:

Infant free school meals in England

Your child will be able to get free school meals if they’re in a government-funded school and in:

Tell your local authority if you also get any of the qualifying benefits. Your child’s school can get extra funding if you do.

https://www.gov.uk/apply-free-school-meals/thurrock