Tested 26.3
The Leather Horse Armor is armor for a horse: put it in the armor slot of a tamed horse's inventory to protect it in fights and falls. It is the only horse armor you can craft, from leather, and the only one you can dye; it gives 3 armor points, and expert leatherworkers sell dyed ones. It works like every other horse armor; the Iron Horse Armor page explains how to equip it.
It is made with the Crafting Table from 7 × Leather (other recipes also exist).
How to craft
1 / 2
Crafting table 
7 × Leather → Leather Horse Armor
Crafting table Any arrangement Also in the 2×2 inventory grid 
Leather Horse Armor + Any of #dyes → Leather Horse Armor
// Slots with several items cycle through every accepted option.
How Leather Horse Armor connects
8 links · from the 26.3 game dataUsed with
Trades
VillagerSold by · Leatherworker (Expert)Same family
Tutorials with Leather Horse Armor (1)
Used to craft (1)
Leather Horse Armor Tags
#minecraft:cauldron_can_remove_dye#minecraft:freeze_immune_wearables
Leather Horse Armor · FAQ
How do you get Leather Horse Armor in Minecraft?
At the Crafting Table: 7 × Leather give 1 × Leather Horse Armor. Sold by Villager: Leatherworker (Expert).
What is Leather Horse Armor used for in Minecraft?
It protects a tamed horse when placed in its armor slot. Worn by: Horse and Zombie Horse.
Does Leather Horse Armor stack?
No: only one per inventory slot.