For established pairs, courtship and nest-building usually start in earnest during March, about 2 - 4 weeks before the first egg is laid, but first-time breeders may not start until April.

Occasionally, inexperienced birds can be seen carrying twigs to nesting sites in fine weather as early as January, although these early attempts to nest generally prove to be ineffectual. The pair will fly together in high circling displays and these will intensify through March.

One of their favourite courtship games is flying towards each other at speed turning and twisting away from each other at the last moment, maybe just touching talons as they pass.
They also have mock talon grappling fights, spinning in mid air, spiralling seemingly out of control toward the ground to part at tree level. These windmilling actions have been known to end fatally, although it is unknown if these fatalities have been caused by over exuberance during courtship, or during genuine fights between males over territorial disputes.

Red Kites are monogamous and pair for life, in fact they tend to stay together at all times except during the winter, so most courtship is the renewing of the bond the pair already have. This tends to help the birds with rearing, as they tend to become more successful with experience.

Welsh Red Kites nests are built exclusively in trees - mostly in hardwoods, such as oaks. Nests are usually built at a height of between 4 and 30 metres above the ground, and are usually fairly flat, untidy structures of sticks, 2 to 3 feet in width.

Both birds assist in the building of the nest which is built of sticks collected from the ground.
Sometimes an old crow's or buzzard's nest will be taken over and renovated but whether new or second hand in Wales the nest lining will always be of sheep's wool.

Kites can be very protective of the actual nest area but not of the whole breeding territory. They tend to keep a home range consisting of the nesting wood, the roost site, and their hunting area.

These home ranges are quite ill defined, vary greatly in size, and may overlap other pairs. The hunting areas for example could range between 2 to 25 Km of the nest area. Throughout this area red kites seem to be tolerant of buzzards and other red kites. Some pairs have even been known to nest within 200 m of each other.

The eggs are normally laid in early April with 1-3 being the usual range. They are produced at 3 day intervals ensuring that there will always be a dominant chick who will be likely to outlive his siblings and hopefully survive himself if food is scarce. Incubation takes 31-32 days with an extra 3 days per extra egg if more than one.

The female carries out the majority of the incubation with relief from the male in the form of several 20 minute breaks during the day for feeding and exercise.
The parent birds must stay alert to protect the eggs from potential nest robbers such as carrion crows and ravens.

It is at this time that the kite is most prone to desertion if disturbed in any way.

The eggs of the Red Kite have been targeted by thieves - collectors will risk very heavy fines (over £1,000) to obtain them. This selfish activity is part of the reason why it took so long for the population to re-establish itself and start expanding again in Wales.

When the chicks hatch the male bird brings food to the nest for the female to tear into small scraps with which to feed them.