diff --git a/src/ca65/ea65.c b/src/ca65/ea65.c
index a1bda2d7b..d030f47b4 100644
--- a/src/ca65/ea65.c
+++ b/src/ca65/ea65.c
@@ -90,7 +90,7 @@ void GetEA (EffAddr* A)
 	/* #val */
 	NextTok ();
 	A->Expr  = Expression ();
-	A->AddrModeSet = AM65_IMM;
+	A->AddrModeSet = AM65_ALL_IMM;
 
     } else if (CurTok.Tok == TOK_A) {
 
@@ -203,4 +203,4 @@ void GetEA (EffAddr* A)
 
 
 
-                           
+
diff --git a/src/ca65/instr.c b/src/ca65/instr.c
index 2cebfecff..c4d756a5d 100644
--- a/src/ca65/instr.c
+++ b/src/ca65/instr.c
@@ -945,17 +945,29 @@ static int EvalEA (const InsDesc* Ins, EffAddr* A)
         A->Expr = SimplifyExpr (A->Expr, &ED);
 
         if (ED.AddrSize == ADDR_SIZE_DEFAULT) {
-            /* If we don't know how big the expression is, assume the
-             * default address size for data. If this default address
-             * size is unequal to zero page addressing, but zero page
-             * addressing is allowed by the instruction, mark all symbols
-             * in the expression tree. This mark will be checked at end
-             * of assembly, and a warning is issued, if a zero page symbol
-             * was guessed wrong here.
+            /* We don't know how big the expression is. If the instruction
+             * allows just one addressing mode, assume this as address size
+             * for the expression. Otherwise assume the default address size
+             * for data.
              */
-            ED.AddrSize = DataAddrSize;
-            if (ED.AddrSize > ADDR_SIZE_ZP && (A->AddrModeSet & AM65_SET_ZP)) {
-                ExprGuessedAddrSize (A->Expr, ADDR_SIZE_ZP);
+            if ((A->AddrModeSet & ~AM65_ALL_ZP) == 0) {
+                ED.AddrSize = ADDR_SIZE_ZP;
+            } else if ((A->AddrModeSet & ~AM65_ALL_ABS) == 0) {
+                ED.AddrSize = ADDR_SIZE_ABS;
+            } else if ((A->AddrModeSet & ~AM65_ALL_FAR) == 0) {
+                ED.AddrSize = ADDR_SIZE_FAR;
+            } else {
+                ED.AddrSize = DataAddrSize;
+                /* If the default address size of the data segment is unequal
+                 * to zero page addressing, but zero page addressing is 
+                 * allowed by the instruction, mark all symbols in the 
+                 * expression tree. This mark will be checked at end of 
+                 * assembly, and a warning is issued, if a zero page symbol
+                 * was guessed wrong here.
+                 */
+                if (ED.AddrSize > ADDR_SIZE_ZP && (A->AddrModeSet & AM65_SET_ZP)) {
+                    ExprGuessedAddrSize (A->Expr, ADDR_SIZE_ZP);
+                }
             }
         }
 
@@ -989,7 +1001,7 @@ static int EvalEA (const InsDesc* Ins, EffAddr* A)
      * emit a warning. This warning protects against a typo, where the '#'
      * for the immediate operand is omitted.
      */
-    if (A->Expr && (Ins->AddrMode & AM65_IMM)                    &&
+    if (A->Expr && (Ins->AddrMode & AM65_ALL_IMM)                &&
         (A->AddrModeSet & (AM65_DIR | AM65_ABS | AM65_ABS_LONG)) &&
         ExtBytes[A->AddrMode] == 1) {
 
diff --git a/src/ca65/instr.h b/src/ca65/instr.h
index aa0a43236..7d39dbeaf 100644
--- a/src/ca65/instr.h
+++ b/src/ca65/instr.h
@@ -82,7 +82,6 @@
 #define AM65_IMM_ACCU	       	0x00200000UL
 #define AM65_IMM_INDEX	       	0x00400000UL
 #define AM65_IMM_IMPLICIT	0x00800000UL
-#define AM65_IMM                (AM65_IMM_ACCU | AM65_IMM_INDEX | AM65_IMM_IMPLICIT)
 #define AM65_BLOCKMOVE          0x01000000UL
 #define AM65_BLOCKXFER          0x02000000UL
 
@@ -90,7 +89,19 @@
 #define AM65_SET_ZP 	(AM65_DIR | AM65_DIR_X | AM65_DIR_Y | AM65_DIR_IND | AM65_DIR_X_IND)
 
 /* Bitmask for all ABS operations that have correspondent FAR ops */
-#define AM65_SET_ABS      (AM65_ABS | AM65_ABS_X)
+#define AM65_SET_ABS    (AM65_ABS | AM65_ABS_X)
+
+/* Bitmask for all ZP operations */
+#define AM65_ALL_ZP     (AM65_DIR | AM65_DIR_X | AM65_DIR_Y | AM65_DIR_IND | AM65_DIR_X_IND)
+
+/* Bitmask for all ABS operations */
+#define AM65_ALL_ABS    (AM65_ABS | AM65_ABS_X | AM65_ABS_Y | AM65_ABS_IND | AM65_ABS_X_IND)
+
+/* Bitmask for all FAR operations */
+#define AM65_ALL_FAR    (AM65_ABS_LONG | AM65_ABS_LONG_X)
+                        
+/* Bitmask for all immediate operations */
+#define AM65_ALL_IMM    (AM65_IMM_ACCU | AM65_IMM_INDEX | AM65_IMM_IMPLICIT)
 
 /* Bit numbers and count */
 #define AM65I_IMM_ACCU	       	21