Peter F. answered 07/13/20
Well-read K-12 Reading Teacher; 18 Years' Teaching Experience
That's a very good question. It really depends on the individual child. Some children have a natural interest/ability in language, and therefore they begin to read earlier than their more mathematically oriented peers. Reading is now taught as early as Kindergarten, so some students are able to read as early as 5 years old. For children younger than 5, in preschool: if their parents read to them a lot, take them to the library (when COVID-19 is not a factor) and get age-appropriate books for them to read at home, and if their preschool teachers introduce them to reading at the simplest level, some children are able to start picking up on reading at ages 3-4. Most children, however, do not really begin digging into books on their own (whether required for school, or pleasure reading on their own time) until age 6-7 after they enter 1st Grade and begin developing their literary skills/literacy more head-on in greater depth than before.
But as long as children are able to enjoy what they read as opposed to have it being nothing more than a school assignment with followup book reports and reading comprehension tests containing lots of pressure, then young people will be able to begin reading naturally and maintain that love of the pastime long-term.