"This is the heart of your village. Upgrading your Town Hall unlocks new defenses, buildings, traps and much more."
Town Hall is the main building of your Home Village. Upgrading it will unlock new Buildings, Troops, Spells, Heroes, and Siege Machines. However, it also changes the Loot Calculation.
Upgrading the Town Hall unlocks many features and makes a big impact on the game. However, it's not recommended to rush the upgrade.
Before upgrading the Town Hall it's highly recommended to upgrade all troops and buildings and it affects the loot and matchmaking.
Town Hall and Matchmaking
Matchmaking is based on Trophies and Town Hall level, except in Champions League and above, where only Trophies matter. Also, the loot available to gain is affected by the Town Hall level. Players get reduced loot for attacking Town Halls of a lower level.
Town Hall and Loot
The game wants you to match against similar Town Hall levels. For this reason there are loot penalties for attacking lower Town Halls. This is done to prevent extreme farming:
Starting on the Summer 2020 Update, upgrading your Town Hall to level 4 and higher gives the player temporary boosts after the upgrade is completed.
Power Boost: Starting from Town Hall 4, your Troops and Spells are temporarily boosted to the maximum level allowed by your Laboratory for a limited time.
Resource Boost: Starting from Town Hall 4, your Resource Collectors are temporarily boosted to work at double their normal rate.
Star Bonus Boost: Starting from Town Hall 4, your Star Bonus rewards from Multiplayer battles are temporarily boosted to 4x.
Hero Boost: Starting from Town Hall 8, your Heroes are temporarily boosted by +5 levels.
The boosts last 3-5 days, depending on the player's new Town Hall level:
Town Hall 4-6 will boost the Town Hall for 3 days.
Town Hall 7-9 will boost the Town Hall for 4 days.
Town Hall 10-13 will boost the Town Hall for 5 days.