diff --git a/src/lm_saes/runner.py b/src/lm_saes/runner.py
index c13eb9af..e5f02247 100644
--- a/src/lm_saes/runner.py
+++ b/src/lm_saes/runner.py
@@ -119,11 +119,22 @@ def language_model_sae_prune_runner(cfg: LanguageModelSAEPruningConfig):
         cache_dir=cfg.lm.cache_dir,
         local_files_only=cfg.lm.local_files_only,
     )
+    hf_tokenizer = AutoTokenizer.from_pretrained(
+        (
+            cfg.lm.model_name
+            if cfg.lm.model_from_pretrained_path is None
+            else cfg.lm.model_from_pretrained_path
+        ),
+        trust_remote_code=True,
+        use_fast=True,
+        add_bos_token=True,
+    )
     model = HookedTransformer.from_pretrained(
         cfg.lm.model_name,
         device=cfg.lm.device,
         cache_dir=cfg.lm.cache_dir,
         hf_model=hf_model,
+        tokenizer=hf_tokenizer,
         dtype=cfg.lm.dtype,
     )
     model.eval()
@@ -239,11 +250,22 @@ def activation_generation_runner(cfg: ActivationGenerationConfig):
         cache_dir=cfg.lm.cache_dir,
         local_files_only=cfg.lm.local_files_only,
     )
+    hf_tokenizer = AutoTokenizer.from_pretrained(
+        (
+            cfg.lm.model_name
+            if cfg.lm.model_from_pretrained_path is None
+            else cfg.lm.model_from_pretrained_path
+        ),
+        trust_remote_code=True,
+        use_fast=True,
+        add_bos_token=True,
+    )
     model = HookedTransformer.from_pretrained(
         cfg.lm.model_name,
         device=cfg.lm.device,
         cache_dir=cfg.lm.cache_dir,
         hf_model=hf_model,
+        tokenizer=hf_tokenizer,
         dtype=cfg.lm.dtype,
     )
     model.eval()