diff --git a/src/c/big.d b/src/c/big.d
index 782a227e5..0026e6c48 100644
--- a/src/c/big.d
+++ b/src/c/big.d
@@ -46,7 +46,10 @@
 void
 _ecl_big_register_free(cl_object x)
 {
-  return;
+  /* We only need to free the integer when it gets too large */
+  if (ECL_BIGNUM_DIM(x) > 4 * ECL_BIG_REGISTER_SIZE) {
+    _ecl_big_realloc2(x, ECL_BIG_REGISTER_SIZE);
+  }
 }
 
 static cl_object
diff --git a/src/h/number.h b/src/h/number.h
index 2a0e94ce5..e2fe43a2f 100644
--- a/src/h/number.h
+++ b/src/h/number.h
@@ -45,6 +45,7 @@ extern ECL_API _ecl_big_binary_op _ecl_big_boole_operator(int op);
 #define _ecl_big_set_index(x, f) mpz_set_ui((x)->big.big_num,(f))
 #endif
 #define _ecl_big_init2(x,size)  mpz_init2((x)->big.big_num,(size)*GMP_LIMB_BITS)
+#define _ecl_big_realloc2(x,size)       mpz_realloc2((x)->big.big_num,(size)*GMP_LIMB_BITS)
 #define _ecl_big_clear(x)       mpz_clear((x)->big.big_num)
 #define _ecl_big_set(x,y)       mpz_set((x)->big.big_num,(y)->big.big_num)
 #define _ecl_big_odd_p(x)       ((mpz_get_ui(x->big.big_num) & 1) != 0)