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As your husband is in the Support Group he is in principle entitled to the Enhanced Disability Premium, providing he is also entitled to an ESA(IR) top-up, the ESA3 captures the information required by the DWP so they can make a Decision on this.
ESA(IR) is dependant on your household income, your savings and assets, and any hours that your partner works. See
Asset rule for ESA(IR) 24 hour work rule for ESA(IR) Your pension will be treated as income.
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