* Heal 3x3: You won't own the square or the what3words address - you're sponsoring it. Read more here. To retain 'your' square or squares and the associated three-word address(es), you will need to pay a small annual 'upkeep' amount of £3 per square, a year after the allocation of the what3words address described on this page. Recurring and one-off donations aren't part of Heal 3x3.