Hi.Recipients of gifts do not pay tax on them. So long as the donor lives for seven years after making the gift, its value will not be part of their estate for Inheritance Tax purposes when they die. If the donor does pass away before the seven year period is completed, the value of gifts made in the seven years before death will be part of the estate for IHT purposes.Take a look here and here for information on IHT exempt gifts. You can give as many gifts of £250 as you like to separate individuals but other gifts cannot exceed £3,000 per annum or up to £6,000 if you have not used your allowance for the previous tax year outside of the allowances for gifts made in recognition of specific events. If you paid £600 per month to your so for his mortgage, then £3,000 would be an exempt gift and the balance of £4,200 would be a potentially exempt transfer and subject to the seven year rule described above and the carry over of any unused allowance from the previous tax year.You can also make gifts out of income but the sum of these gifts must not impact on the lifestyle to which you are used to maintaining. If your late husband's estate did not use any of his IHT exemption, then that can be transferred to your estate when you die. As of now, the double exemption would be £650,000.I hope this helps but let me know if you have any further questions.