diff --git a/config.py b/config.py
index f638681..955ad2e 100644
--- a/config.py
+++ b/config.py
@@ -196,9 +196,25 @@ class PlatformConfig:
     # Twelve Data API key (overridden by TWELVE_DATA_API_KEY env var)
     twelve_data_api_key: str = "f563b22ffdfd4924955decbe1a8c8701"
 
-    # Dashboard refresh interval (seconds)
+    # Dashboard refresh interval (seconds) — used as a fallback when a
+    # timeframe isn't covered by cache_ttl_per_tf below.
     refresh_interval: int = 300  # 5 minutes
 
+    # Per-timeframe cache TTL (seconds). A 1-week candle changes less
+    # often than a 15-minute candle, so caching them all for the same
+    # 5 minutes wastes API credits. Tuned to roughly match each TF's
+    # bar interval so we re-fetch about once per new bar.
+    cache_ttl_per_tf: Dict[Timeframe, int] = field(default_factory=lambda: {
+        Timeframe.M1:  60,         # 1 minute
+        Timeframe.M5:  150,        # 2.5 minutes
+        Timeframe.M15: 300,        # 5 minutes
+        Timeframe.M30: 600,        # 10 minutes
+        Timeframe.H1:  1800,       # 30 minutes
+        Timeframe.H4:  7200,       # 2 hours
+        Timeframe.D1:  14400,      # 4 hours
+        Timeframe.W1:  86400,      # 24 hours
+    })
+
     # Logging
     log_level: str = "INFO"
     log_signals_to_file: bool = True
diff --git a/data_provider.py b/data_provider.py
index da28e95..aa24073 100644
--- a/data_provider.py
+++ b/data_provider.py
@@ -125,6 +125,10 @@ class ForexDataProvider:
         clean = symbol.replace("=X", "")
         return f"{clean[:3]}/{clean[3:]}"
 
+    def _cache_ttl(self, timeframe: Timeframe) -> int:
+        """Cache TTL for a given timeframe — falls back to refresh_interval."""
+        return self.config.cache_ttl_per_tf.get(timeframe, self.config.refresh_interval)
+
     def fetch_ohlcv(
         self,
         symbol: str,
@@ -142,10 +146,11 @@ class ForexDataProvider:
 
         cache_key = f"{symbol}_{timeframe.value}"
         now = time.time()
+        ttl = self._cache_ttl(timeframe)
 
         if (
             cache_key in self._cache_timestamps
-            and (now - self._cache_timestamps[cache_key]) < self.config.refresh_interval
+            and (now - self._cache_timestamps[cache_key]) < ttl
             and cache_key in self._cache
         ):
             cached = self._cache.get(cache_key)
@@ -178,14 +183,15 @@ class ForexDataProvider:
 
         now = time.time()
         for tf in timeframes:
+            ttl = self._cache_ttl(tf)
             cached = all(
                 f"{s}_{tf.value}" in self._cache_timestamps
-                and (now - self._cache_timestamps[f"{s}_{tf.value}"]) < self.config.refresh_interval
+                and (now - self._cache_timestamps[f"{s}_{tf.value}"]) < ttl
                 and not self._cache.get(f"{s}_{tf.value}", pd.DataFrame()).empty
                 for s in symbols
             )
             if cached:
-                logger.debug(f"Skipping prefetch for {tf.value} — all {len(symbols)} symbols cached")
+                logger.debug(f"Skipping prefetch for {tf.value} — all {len(symbols)} symbols cached (TTL {ttl}s)")
                 continue
             try:
                 self._batch_fetch_timeframe(symbols, tf, lookback_days)