Hammer Jam 2026 and Town Hall 19 Prep Guide: Why You Should Save Potions, Not Hammers (Clash of Clans)

Quick answer: The best Hammer Jam prep is to stockpile Builder, Research and Pet Potions (5 of each, the normal cap) for the event and to use Hammers and Books before or after it, not during it (except a Book that frees a Builder late in the Jam), because Hammer Jam halves upgrade costs and times — the last one ran November 1–17, 2025 at 50% off — so a potion's 9 or 23 extra hours of work cover twice as much upgrade time, while a Hammer or Book only saves the already-halved timer.

Hammer Jam is Clash of Clans' pre-Town-Hall upgrade sale, and the last one ran 17 days, November 1–17, 2025, with 50% off upgrade costs and times, double Resource Collector capacity and production, and the Goblin Builder and Goblin Researcher in the village all month; Town Hall 18 followed on November 17, 2025, and Town Hall 17 on November 25, 2024. Supercell has not announced Hammer Jam 2026 or Town Hall 19 as of October 6, 2026. What exists is creator reporting: Judo Sloth Gaming's October 4 video "TH19 Info, Prepare for Hammer Jam Now!" — over 1,000,000 views in 2 days — relays Supercell staff saying Town Halls still follow a 12-month cycle and that Hammer Jam will not be A/B tested. This guide separates what is confirmed from what is reported, and turns the confirmed rules into a prep plan.

What Is Confirmed About Hammer Jam 2026 and Town Hall 19?

Nothing about Hammer Jam 2026 or Town Hall 19 is confirmed by Supercell yet. Everything below is either Supercell's record from past years or a creator's report of what Supercell staff told him, labeled as such.

So the working assumption — a Hammer Jam in early November and Town Hall 19 a few weeks later — rests on 2 Novembers of precedent and a reported 12-month cycle, not an announcement.

What Did the Last Hammer Jam Change?

Hammer Jam 2025 cut upgrade costs and times by 50% for every Town Hall level, with 2 exclusions: Supercharges and Crafted Defenses. Supercell's November 1, 2025 post listed 4 rules:

Earlier Jams varied. Per the Clash of Clans Wiki's event history, the 2023 Hammer Jam before Town Hall 16 discounted buildings and traps but not Hero upgrades, and the 2024 Hammer Jam before Town Hall 17 covered buildings, traps and Heroes, costs and times, with Collectors at 3×. The 2025 version's "all upgrades except Supercharges and Crafted Defenses" is the most recent rule, so it is the one to plan around until Supercell posts 2026's.

One reported pattern is worth knowing: Judo Sloth notes that recent Jams have lasted as many days as the highest Town Hall — 17 days at Town Hall 17, which matches 2025's official November 1–17 window. Supercell has never stated that rule.

Why Do Potions Beat Hammers During Hammer Jam?

Potions beat Hammers during Hammer Jam because the discount moves their values in opposite directions — the question is not which item is better overall, but when each one is worth the most. Potions gain because a potion adds work time, and every hour of work covers twice as much of a halved timer, while a Hammer or Book skips a timer that the discount has already halved. The magic-item effects, per the Clash of Clans Wiki's item list:

The arithmetic for the Builder Potion: 1 hour at 10× speed is 10 hours of progress, 9 more than the Builder would have done. During a 50% Hammer Jam those 9 hours finish what is normally an 18-hour stretch of timer, so the same potion is worth double. Applied to all 6 Builders at once — Judo Sloth counts the 6th Builder from the Builder Base as a must-have before the event — one Builder Potion covers 108 hours of normal-length timers during the Jam, against 54 hours outside it.

The Hammer runs the other way. A Hammer of Building used today on an upgrade with a 10-day timer saves 10 days of Builder time and the full cost. Used on the same upgrade during a 50% Jam, it saves 5 days and half the cost. Books behave the same: they finish the remaining timer, and the Jam has already cut it in half. Hammers and Books are worth most outside the event; potions are worth most inside it. That leaves 3 choices for a Hammer or Book, and 1 of them is usually the weakest:

Magic Hammers cap at 1 of each type per the wiki and come only from the League Shop, so holding one through the Jam costs nothing unless another would arrive over the cap. Spend it before the event if your account is far from TH19; keep it for after if you will upgrade the Town Hall as soon as TH19 lands.

Per item, the Research Potion covers the most lab time — 46 hours of normal-length research per use during a 50% Jam — though a single Builder Potion covers more in total (108 hours across 6 Builders) because it boosts every Builder at once. Judo Sloth makes the point that with the Goblin Researcher also active, the Laboratory runs 2 research jobs at once, so a Research Potion boosts both — the lab version of adding a Builder.

What Should You Stockpile Before Hammer Jam?

Stockpile anything whose value scales with the discount, and spend anything whose value shrinks with it. In order:

1. Builder, Research and Pet Potions — fill each to 5. 5 is the normal capacity for each potion per the wiki; only special Shop offers can push past it. If an event or Gold Pass hands you a 6th, use 1 rather than selling it, so the stack stays at 5.
2. Gems for the Goblin Builder and Goblin Researcher. Both returned for all of November 2025. Judo Sloth's advice is to clear obstacles in both villages, sell magic items you will never use, and claim the free monthly Supercell Store mission gems to build a reserve.
3. Medals for potions. Judo Sloth recommends banking Clan War League medals through October (for Builder Potions, not Hammers) and Raid Medals toward their caps (for Research and Pet Potions).
4. A farming army you have upgraded. Halved costs mean more upgrades per day, so the bottleneck moves from time to loot. Pick your fastest farming army now — Judo Sloth uses Valkyries with Earthquake Spells; Sneaky Goblins, Dragons and Electro Dragons all work — and upgrade it before the Jam.
5. Full storages on day one. Stop spending loot in the last days before the event and enter it with full Gold, Elixir and Dark Elixir storages, so the first round of half-price upgrades starts the moment the Jam does; then collect the Collectors often, since they ran at 2× capacity and production in 2025.

What Should You Finish Now at Town Hall 17 and Town Hall 18?

Finish the upgrades that Hammer Jam did not discount in 2025, and time your last full-price upgrades to end before the event, so no Builder is stuck on a full-price job when half-price ones open. Supercharges and Crafted Defenses were excluded in 2025, so there is no reason to save them.

The caps are the TrophyCoach Upgrade Priority tool's hero table, current through the Town Hall 18 update. Start the longest Hero upgrades during the Jam rather than before it: in 2025 Heroes were included in the discount, so a long Hero timer started on November 1 cost half of one started in October.

At Town Hall 18, Judo Sloth reports Supercell telling him that Guardians move out of the Town Hall at TH19 — into another building or their own flag — and that you will not need maxed Guardians to upgrade to TH19. Supercell has not confirmed this; treat it as a reason not to rush Guardian levels ahead of heroes and core defenses, not as a plan for TH19.

A simple cutoff rule. If 2026 follows 2025's November 1 start, any full-price upgrade whose timer runs past October 31 holds a Builder out of the half-price window. Subtract the timer from October 31: a 14-day upgrade should start by October 17, a 7-day upgrade by October 24. Shorter jobs can fill the gap until the Jam starts.

If the 2026 rules differ. The 2023 Hammer Jam excluded Hero upgrades; 2024 and 2025 included them. If Supercell's 2026 post excludes Heroes again, keep Hero upgrades running as normal and point every potion and Gem at buildings and the Laboratory instead. If the discount is not 50%, scale the potion arithmetic above by the new rate — at 30% off, for example, a Builder Potion's 9 hours cover about 12.9 hours of normal-length timer.

Town Hall 17 versus Town Hall 18. A Town Hall 17 account has the most to gain from a 50% Jam on its remaining TH17 buildings and Heroes before deciding when to move to TH18. A Town Hall 18 account at or near its caps should treat the Jam as the moment to finish the last TH18 levels and to hold resources for whatever TH19 adds, which Supercell has not yet described.

For the general order of what to upgrade first at each Town Hall, see our upgrade priority guide and the hero upgrade order guide.

When Will Hammer Jam 2026 and Town Hall 19 Arrive?

Hammer Jam 2026 and Town Hall 19 have no release dates as of October 6, 2026. The 2 previous Town Halls landed on November 25, 2024 (TH17) and November 17, 2025 (TH18), and the 2025 Hammer Jam started on November 1. If the reported 12-month cycle holds, both land in November 2026, with the Jam first. The October 2026 season (Cosmic Curse: Portal Panic) runs to October 31 and contains no Hammer Jam, per Supercell's October 1 season post; our October 2026 season guide lists every October date.

This page will add the 2026 dates, discount and exclusions the day Supercell posts them.

What Are the Most Common Hammer Jam Prep Mistakes?

Mistake 1 — Using Builder Potions in October. A Builder Potion used now covers 9 hours per Builder; held for a 50% Jam it covers 18. Use one now only when your stack is already at 5 and another is about to arrive.

Mistake 2 — Using Hammers during the Jam. A Hammer of Building saves the full cost and time of an upgrade before or after the Jam and half of both during it. Use it before the event, or hold it for Town Hall 19 — not in between.

Mistake 3 — Starting long full-price upgrades in late October. A building upgrade with weeks left on its timer when the Jam starts keeps that Builder out of the half-price window.

Mistake 4 — Spending Gems on permanent helpers now. Judo Sloth's advice is to hold Gems for the Goblin Builder and Goblin Researcher during the event rather than upgrading helpers in October, because a short event rewards extra workers more than slow long-term boosts.

Mistake 5 — Planning around unannounced TH19 content. Supercell has published no TH19 buildings, levels or costs. Any upgrade plan that depends on them is guesswork until the release notes arrive.

Frequently Asked Questions

When is Hammer Jam 2026?

Hammer Jam 2026 has not been announced as of October 6, 2026. The last Hammer Jam ran November 1–17, 2025 and ended the day Town Hall 18 released, so early November 2026 is the likely window if the pattern repeats.

When is Town Hall 19 coming out?

Town Hall 19 has no official release date. Judo Sloth Gaming reported on October 4, 2026 that Supercell is keeping a 12-month Town Hall cycle; Town Hall 17 released November 25, 2024 and Town Hall 18 on November 17, 2025.

Should I save Builder Potions or Hammers for Hammer Jam?

Save Builder Potions for Hammer Jam, and use Hammers before the event or after it on Town Hall 19 upgrades. During a 50% Hammer Jam a Builder Potion's 9 extra hours per Builder cover 18 hours of normal-length timers, while a Hammer of Building saves half the cost and time it would save today.

How much did Hammer Jam 2025 discount?

Hammer Jam 2025 discounted upgrade costs and times by 50% for every Town Hall level, from November 1 to 17, 2025, excluding Supercharges and Crafted Defenses. Resource Collectors also had 2× capacity and production.

Are Research Potions better than Builder Potions during Hammer Jam?

Research Potions give the most per worker: 1 hour at 24× is 23 extra hours of lab work, covering 46 hours of normal-length research during a 50% Jam. Builder Potions give the most in total, covering 18 hours per Builder — 108 hours across 6 Builders — because they boost every Builder at once.

How long did Hammer Jam 2025 last?

Hammer Jam 2025 lasted 17 days, from November 1 to November 17, 2025, per Supercell's November 1 post; it ended the day Town Hall 18 released.

Will Guardians be removed at Town Hall 19?

Guardians are not being removed, according to Judo Sloth Gaming's October 4, 2026 report: he says Supercell told him Guardians stay at Town Hall 19 but move out of the Town Hall into another building or their own flag. Supercell has not confirmed it.