diff --git a/asm/mail.s b/asm/mail.s
index 5f76a5ef0..7ae0b78d6 100644
--- a/asm/mail.s
+++ b/asm/mail.s
@@ -5,164 +5,6 @@
 
 	.text
 
-	thumb_func_start sub_8121478
-sub_8121478: @ 8121478
-	push {r4-r7,lr}
-	sub sp, 0x4
-	adds r5, r0, 0
-	adds r7, r1, 0
-	lsls r2, 24
-	lsrs r6, r2, 24
-	ldr r4, =gUnknown_0203A134
-	ldr r0, =0x0000222c
-	bl AllocZeroed
-	str r0, [r4]
-	ldr r1, =0x0000021d
-	adds r0, r1
-	movs r1, 0x2
-	strb r1, [r0]
-	ldr r0, [r4]
-	ldr r2, =0x0000021e
-	adds r0, r2
-	movs r1, 0x1
-	strb r1, [r0]
-	ldr r4, [r4]
-	movs r3, 0x88
-	lsls r3, 2
-	adds r1, r4, r3
-	ldr r0, =CopyEasyChatWord
-	str r0, [r1]
-	movs r0, 0x89
-	lsls r0, 2
-	adds r1, r4, r0
-	ldr r0, =ConvertEasyChatWordsToString
-	str r0, [r1]
-	ldrh r1, [r5, 0x20]
-	adds r0, r1, 0
-	subs r0, 0x79
-	lsls r0, 16
-	lsrs r0, 16
-	cmp r0, 0xB
-	bhi _081214E8
-	subs r1, 0x79
-	subs r2, 0x4
-	adds r0, r4, r2
-	strb r1, [r0]
-	b _081214F2
-	.pool
-_081214E8:
-	ldr r3, =0x0000021a
-	adds r1, r4, r3
-	movs r0, 0
-	strb r0, [r1]
-	movs r6, 0
-_081214F2:
-	ldr r0, =gUnknown_0203A134
-	ldr r1, [r0]
-	ldr r2, =0x0000021e
-	adds r0, r1, r2
-	ldrb r0, [r0]
-	cmp r0, 0
-	beq _08121504
-	cmp r0, 0x1
-	beq _0812152C
-_08121504:
-	movs r3, 0x8A
-	lsls r3, 2
-	adds r2, r1, r3
-	subs r3, 0xE
-	adds r0, r1, r3
-	ldrb r1, [r0]
-	lsls r0, r1, 1
-	adds r0, r1
-	lsls r0, 2
-	ldr r1, =gUnknown_0859F3B4
-	b _08121540
-	.pool
-_0812152C:
-	movs r0, 0x8A
-	lsls r0, 2
-	adds r2, r1, r0
-	ldr r3, =0x0000021a
-	adds r0, r1, r3
-	ldrb r1, [r0]
-	lsls r0, r1, 1
-	adds r0, r1
-	lsls r0, 2
-	ldr r1, =gUnknown_0859F458
-_08121540:
-	adds r0, r1
-	str r0, [r2]
-	ldrh r0, [r5, 0x1E]
-	mov r1, sp
-	bl sub_80D45E8
-	lsls r0, 16
-	ldr r1, =0xffff0000
-	adds r0, r1
-	movs r1, 0xCD
-	lsls r1, 17
-	cmp r0, r1
-	bhi _081215AC
-	ldr r1, =gUnknown_0203A134
-	ldr r2, [r1]
-	ldr r3, =0x0000021a
-	adds r0, r2, r3
-	ldrb r0, [r0]
-	adds r3, r1, 0
-	cmp r0, 0x6
-	beq _0812158C
-	cmp r0, 0x9
-	beq _0812159C
-	ldr r0, =0x0000021b
-	adds r1, r2, r0
-	movs r0, 0
-	strb r0, [r1]
-	b _081215BA
-	.pool
-_0812158C:
-	ldr r0, =0x0000021b
-	adds r1, r2, r0
-	movs r0, 0x1
-	strb r0, [r1]
-	b _081215BA
-	.pool
-_0812159C:
-	ldr r0, =0x0000021b
-	adds r1, r2, r0
-	movs r0, 0x2
-	strb r0, [r1]
-	b _081215BA
-	.pool
-_081215AC:
-	ldr r0, =gUnknown_0203A134
-	ldr r1, [r0]
-	ldr r2, =0x0000021b
-	adds r1, r2
-	movs r2, 0
-	strb r2, [r1]
-	adds r3, r0, 0
-_081215BA:
-	ldr r1, [r3]
-	movs r3, 0x85
-	lsls r3, 2
-	adds r0, r1, r3
-	str r5, [r0]
-	movs r2, 0x83
-	lsls r2, 2
-	adds r0, r1, r2
-	str r7, [r0]
-	adds r3, 0x4
-	adds r0, r1, r3
-	strb r6, [r0]
-	ldr r0, =sub_81219F0
-	bl SetMainCallback2
-	add sp, 0x4
-	pop {r4-r7}
-	pop {r0}
-	bx r0
-	.pool
-	thumb_func_end sub_8121478
-
 	thumb_func_start sub_81215EC
 sub_81215EC: @ 81215EC
 	push {r4-r6,lr}
diff --git a/include/easy_chat.h b/include/easy_chat.h
index fc44b6a8a..c9ba81c6d 100644
--- a/include/easy_chat.h
+++ b/include/easy_chat.h
@@ -30,7 +30,8 @@ enum
 
 void InitEasyChatPhrases(void);
 void easy_chat_input_maybe(void);
-void CopyEasyChatWord(u8 *, u16);
+void CopyEasyChatWord(u8 *dest, u16 word);
+void ConvertEasyChatWordsToString(u8 *dest, const u16 *src, u16 length1, u16 length2);
 bool32 sub_811F8D8(u16);
 
 #endif // GUARD_EASYCHAT_H
diff --git a/include/mail_data.h b/include/mail_data.h
new file mode 100644
index 000000000..bf6540bad
--- /dev/null
+++ b/include/mail_data.h
@@ -0,0 +1,12 @@
+#ifndef GUARD_MAIL_DATA_H
+#define GUARD_MAIL_DATA_H
+
+// Exported type declarations
+
+// Exported RAM declarations
+
+// Exported ROM declarations
+
+u16 sub_80D45E8(u16, u16 *);
+
+#endif //GUARD_MAIL_DATA_H
diff --git a/include/malloc.h b/include/malloc.h
index 4568e244a..f3a731797 100644
--- a/include/malloc.h
+++ b/include/malloc.h
@@ -2,7 +2,7 @@
 #define GUARD_MALLOC_H
 
 #define malloc Alloc
-#define calloc AllocZeroed
+#define calloc(ct, sz) AllocZeroed((ct) * (sz))
 #define free Free
 
 extern u8 gHeap[];
diff --git a/ld_script.txt b/ld_script.txt
index 3e47864f1..dfc790530 100644
--- a/ld_script.txt
+++ b/ld_script.txt
@@ -164,6 +164,7 @@ SECTIONS {
         asm/easy_chat.o(.text);
         asm/mon_markings.o(.text);
         asm/mauville_old_man.o(.text);
+        src/mail.o(.text);
         asm/mail.o(.text);
         asm/menu_helpers.o(.text);
         asm/dewford_trend.o(.text);
diff --git a/src/mail.c b/src/mail.c
new file mode 100644
index 000000000..a21a297b6
--- /dev/null
+++ b/src/mail.c
@@ -0,0 +1,127 @@
+
+// Includes
+#include "global.h"
+#include "main.h"
+#include "species.h"
+#include "malloc.h"
+#include "easy_chat.h"
+#include "mail_data.h"
+#include "mail.h"
+
+// Static type declarations
+
+struct UnkMailStruct
+{
+    u8 unk_0_0:2;
+    u8 unk_0_2:2;
+    u8 unk_0_4:4;
+};
+
+struct MailLayout
+{
+    u8 var0;
+    u8 var1;
+    u8 var2;
+    u8 var3_0:4;
+    u8 var3_4:4;
+    struct UnkMailStruct *var4;
+    u32 var8;
+};
+
+struct Unk203A134
+{
+    /*0x0000*/ u8 filler_0000[0x20c];
+    /*0x020C*/ MainCallback callback;
+    /*0x0210*/ u8 filler_0210[4];
+    /*0x0214*/ struct MailStruct *mail;
+    /*0x0218*/ bool8 flag;
+    /*0x0219*/ u8 filler_0219[1];
+    /*0x021a*/ u8 mailType;
+    /*0x021b*/ u8 unk_021b;
+    /*0x021c*/ u8 unk_021c;
+    /*0x021d*/ u8 language;
+    /*0x021e*/ bool8 playerIsSender;
+    /*0x0220*/ void (*parserSingle)(u8 *dest, u16 word);
+    /*0x0224*/ void (*parserMultiple)(u8 *dest, const u16 *src, u16 length1, u16 length2);
+    /*0x0228*/ const struct MailLayout *layout;
+    /*0x022c*/ u8 filler_022C[0x2000];
+};
+
+struct MailGraphics
+{
+    u16 (*palette)[];
+    u8 (*tiles)[];
+    u8 (*tileMap)[];
+    u16 var0C;
+    u16 var0E;
+    u16 color10;
+    u16 color12;
+};
+
+// Static RAM declarations
+
+EWRAM_DATA struct Unk203A134 *gUnknown_0203A134;
+
+// Static ROM declarations
+
+void sub_81219F0(void);
+
+// .rodata
+
+extern const struct MailLayout gUnknown_0859F3B4[];
+extern const struct MailLayout gUnknown_0859F458[];
+
+// .text
+
+void sub_8121478(struct MailStruct *mail, MainCallback callback, bool8 flag) {
+    u16 buffer[2];
+    u16 species;
+
+    gUnknown_0203A134 = calloc(1, sizeof(struct Unk203A134));
+    gUnknown_0203A134->language = LANGUAGE_ENGLISH;
+    gUnknown_0203A134->playerIsSender = TRUE;
+    gUnknown_0203A134->parserSingle = CopyEasyChatWord;
+    gUnknown_0203A134->parserMultiple = ConvertEasyChatWordsToString;
+    if (mail->itemId >= ITEM_ORANGE_MAIL && mail->itemId <= ITEM_RETRO_MAIL) {
+        gUnknown_0203A134->mailType = mail->itemId - ITEM_ORANGE_MAIL;
+    }
+    else
+    {
+        gUnknown_0203A134->mailType = 0;
+        flag = FALSE;
+    }
+    switch (gUnknown_0203A134->playerIsSender)
+    {
+        case FALSE:
+        default:
+            gUnknown_0203A134->layout = &gUnknown_0859F3B4[gUnknown_0203A134->mailType];
+            break;
+        case TRUE:
+            gUnknown_0203A134->layout = &gUnknown_0859F458[gUnknown_0203A134->mailType];
+            break;
+    }
+    species = sub_80D45E8(mail->species, buffer);
+    if (species >= SPECIES_BULBASAUR && species < NUM_SPECIES)
+    {
+        switch (gUnknown_0203A134->mailType)
+        {
+            default:
+                gUnknown_0203A134->unk_021b = 0;
+                break;
+            case ITEM_BEAD_MAIL - ITEM_ORANGE_MAIL:
+                gUnknown_0203A134->unk_021b = 1;
+                break;
+            case ITEM_DREAM_MAIL - ITEM_ORANGE_MAIL:
+                gUnknown_0203A134->unk_021b = 2;
+                break;
+        }
+    }
+    else
+    {
+        gUnknown_0203A134->unk_021b = 0;
+    }
+    gUnknown_0203A134->mail = mail;
+    gUnknown_0203A134->callback = callback;
+    gUnknown_0203A134->flag = flag;
+    SetMainCallback2(sub_81219F0);
+}