diff --git a/src/arch/z80/backend/common.py b/src/arch/z80/backend/common.py
index 436413833..6f25dc8d2 100644
--- a/src/arch/z80/backend/common.py
+++ b/src/arch/z80/backend/common.py
@@ -385,19 +385,24 @@ def to_long(stype: DataType) -> list[str]:
         )
         return output
 
-    if stype in {I8_t, U8_t, F16_t}:  # Byte to word
+    if stype in (I8_t, U8_t):  # Byte to word
         output = to_word(stype)
+        output.append("ld e, h")
+        output.append("ld d, h")
 
-        if stype != F16_t:  # If it's a byte, just copy H to D,E
-            output.append("ld e, h")
-            output.append("ld d, h")
+    elif stype == I16_t:  # Signed byte or fixed to word
+        output.extend(
+            [
+                "ld a, h",
+                "add a, a",
+                "sbc a, a",
+                "ld e, a",
+                "ld d, a",
+            ]
+        )
 
-    elif stype in (I16_t, F16_t):  # Signed byte or fixed to word
-        output.append("ld a, h")
-        output.append("add a, a")
-        output.append("sbc a, a")
-        output.append("ld e, a")
-        output.append("ld d, a")
+    elif stype == F16_t:
+        output.extend(["ex de, hl", "ld de, 0"])
 
     elif stype in (U32_t, I32_t):
         return []
diff --git a/tests/functional/arch/zx48k/cast_f16_to_long.asm b/tests/functional/arch/zx48k/cast_f16_to_long.asm
new file mode 100644
index 000000000..547845bad
--- /dev/null
+++ b/tests/functional/arch/zx48k/cast_f16_to_long.asm
@@ -0,0 +1,49 @@
+	org 32768
+.core.__START_PROGRAM:
+	di
+	push ix
+	push iy
+	exx
+	push hl
+	exx
+	ld (.core.__CALL_BACK__), sp
+	ei
+	jp .core.__MAIN_PROGRAM__
+.core.__CALL_BACK__:
+	DEFW 0
+.core.ZXBASIC_USER_DATA:
+	; Defines USER DATA Length in bytes
+.core.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_END - .core.ZXBASIC_USER_DATA
+	.core.__LABEL__.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_LEN
+	.core.__LABEL__.ZXBASIC_USER_DATA EQU .core.ZXBASIC_USER_DATA
+_v1:
+	DEFB 00h
+	DEFB 80h
+	DEFB 01h
+	DEFB 00h
+_v2:
+	DEFB 00, 00, 00, 00
+.core.ZXBASIC_USER_DATA_END:
+.core.__MAIN_PROGRAM__:
+	ld hl, (_v1)
+	ld de, (_v1 + 2)
+	ex de, hl
+	ld de, 0
+	ld (_v2), hl
+	ld (_v2 + 2), de
+	ld hl, 0
+	ld b, h
+	ld c, l
+.core.__END_PROGRAM:
+	di
+	ld hl, (.core.__CALL_BACK__)
+	ld sp, hl
+	exx
+	pop hl
+	exx
+	pop iy
+	pop ix
+	ei
+	ret
+	;; --- end of user code ---
+	END
diff --git a/tests/functional/arch/zx48k/cast_f16_to_long.bas b/tests/functional/arch/zx48k/cast_f16_to_long.bas
new file mode 100644
index 000000000..b8f1315d7
--- /dev/null
+++ b/tests/functional/arch/zx48k/cast_f16_to_long.bas
@@ -0,0 +1,5 @@
+DIM v1 As Fixed = 1.5
+DIM v2 As Long
+
+v2 = v1
+
diff --git a/tests/functional/arch/zx48k/cast_f16_to_ulong.asm b/tests/functional/arch/zx48k/cast_f16_to_ulong.asm
new file mode 100644
index 000000000..547845bad
--- /dev/null
+++ b/tests/functional/arch/zx48k/cast_f16_to_ulong.asm
@@ -0,0 +1,49 @@
+	org 32768
+.core.__START_PROGRAM:
+	di
+	push ix
+	push iy
+	exx
+	push hl
+	exx
+	ld (.core.__CALL_BACK__), sp
+	ei
+	jp .core.__MAIN_PROGRAM__
+.core.__CALL_BACK__:
+	DEFW 0
+.core.ZXBASIC_USER_DATA:
+	; Defines USER DATA Length in bytes
+.core.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_END - .core.ZXBASIC_USER_DATA
+	.core.__LABEL__.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_LEN
+	.core.__LABEL__.ZXBASIC_USER_DATA EQU .core.ZXBASIC_USER_DATA
+_v1:
+	DEFB 00h
+	DEFB 80h
+	DEFB 01h
+	DEFB 00h
+_v2:
+	DEFB 00, 00, 00, 00
+.core.ZXBASIC_USER_DATA_END:
+.core.__MAIN_PROGRAM__:
+	ld hl, (_v1)
+	ld de, (_v1 + 2)
+	ex de, hl
+	ld de, 0
+	ld (_v2), hl
+	ld (_v2 + 2), de
+	ld hl, 0
+	ld b, h
+	ld c, l
+.core.__END_PROGRAM:
+	di
+	ld hl, (.core.__CALL_BACK__)
+	ld sp, hl
+	exx
+	pop hl
+	exx
+	pop iy
+	pop ix
+	ei
+	ret
+	;; --- end of user code ---
+	END
diff --git a/tests/functional/arch/zx48k/cast_f16_to_ulong.bas b/tests/functional/arch/zx48k/cast_f16_to_ulong.bas
new file mode 100644
index 000000000..e805c2240
--- /dev/null
+++ b/tests/functional/arch/zx48k/cast_f16_to_ulong.bas
@@ -0,0 +1,5 @@
+DIM v1 As Fixed = 1.5
+DIM v2 As ULong
+
+v2 = v1
+
diff --git a/tests/functional/arch/zxnext/cast_f16_to_long.asm b/tests/functional/arch/zxnext/cast_f16_to_long.asm
new file mode 100644
index 000000000..53c65b0ce
--- /dev/null
+++ b/tests/functional/arch/zxnext/cast_f16_to_long.asm
@@ -0,0 +1,42 @@
+	org 32768
+.core.__START_PROGRAM:
+	di
+	push iy
+	ld iy, 0x5C3A  ; ZX Spectrum ROM variables address
+	ld (.core.__CALL_BACK__), sp
+	ei
+	jp .core.__MAIN_PROGRAM__
+.core.__CALL_BACK__:
+	DEFW 0
+.core.ZXBASIC_USER_DATA:
+	; Defines USER DATA Length in bytes
+.core.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_END - .core.ZXBASIC_USER_DATA
+	.core.__LABEL__.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_LEN
+	.core.__LABEL__.ZXBASIC_USER_DATA EQU .core.ZXBASIC_USER_DATA
+_v1:
+	DEFB 00h
+	DEFB 80h
+	DEFB 01h
+	DEFB 00h
+_v2:
+	DEFB 00, 00, 00, 00
+.core.ZXBASIC_USER_DATA_END:
+.core.__MAIN_PROGRAM__:
+	ld hl, (_v1)
+	ld de, (_v1 + 2)
+	ex de, hl
+	ld de, 0
+	ld (_v2), hl
+	ld (_v2 + 2), de
+	ld hl, 0
+	ld b, h
+	ld c, l
+.core.__END_PROGRAM:
+	di
+	ld hl, (.core.__CALL_BACK__)
+	ld sp, hl
+	pop iy
+	ei
+	ret
+	;; --- end of user code ---
+	END
diff --git a/tests/functional/arch/zxnext/cast_f16_to_long.bas b/tests/functional/arch/zxnext/cast_f16_to_long.bas
new file mode 100644
index 000000000..b8f1315d7
--- /dev/null
+++ b/tests/functional/arch/zxnext/cast_f16_to_long.bas
@@ -0,0 +1,5 @@
+DIM v1 As Fixed = 1.5
+DIM v2 As Long
+
+v2 = v1
+
diff --git a/tests/functional/arch/zxnext/cast_f16_to_ulong.asm b/tests/functional/arch/zxnext/cast_f16_to_ulong.asm
new file mode 100644
index 000000000..53c65b0ce
--- /dev/null
+++ b/tests/functional/arch/zxnext/cast_f16_to_ulong.asm
@@ -0,0 +1,42 @@
+	org 32768
+.core.__START_PROGRAM:
+	di
+	push iy
+	ld iy, 0x5C3A  ; ZX Spectrum ROM variables address
+	ld (.core.__CALL_BACK__), sp
+	ei
+	jp .core.__MAIN_PROGRAM__
+.core.__CALL_BACK__:
+	DEFW 0
+.core.ZXBASIC_USER_DATA:
+	; Defines USER DATA Length in bytes
+.core.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_END - .core.ZXBASIC_USER_DATA
+	.core.__LABEL__.ZXBASIC_USER_DATA_LEN EQU .core.ZXBASIC_USER_DATA_LEN
+	.core.__LABEL__.ZXBASIC_USER_DATA EQU .core.ZXBASIC_USER_DATA
+_v1:
+	DEFB 00h
+	DEFB 80h
+	DEFB 01h
+	DEFB 00h
+_v2:
+	DEFB 00, 00, 00, 00
+.core.ZXBASIC_USER_DATA_END:
+.core.__MAIN_PROGRAM__:
+	ld hl, (_v1)
+	ld de, (_v1 + 2)
+	ex de, hl
+	ld de, 0
+	ld (_v2), hl
+	ld (_v2 + 2), de
+	ld hl, 0
+	ld b, h
+	ld c, l
+.core.__END_PROGRAM:
+	di
+	ld hl, (.core.__CALL_BACK__)
+	ld sp, hl
+	pop iy
+	ei
+	ret
+	;; --- end of user code ---
+	END
diff --git a/tests/functional/arch/zxnext/cast_f16_to_ulong.bas b/tests/functional/arch/zxnext/cast_f16_to_ulong.bas
new file mode 100644
index 000000000..e805c2240
--- /dev/null
+++ b/tests/functional/arch/zxnext/cast_f16_to_ulong.bas
@@ -0,0 +1,5 @@
+DIM v1 As Fixed = 1.5
+DIM v2 As ULong
+
+v2 = v1
+