diff --git a/fuzzterm.c b/fuzzterm.c
index cfb80a63..c1fc2b3c 100644
--- a/fuzzterm.c
+++ b/fuzzterm.c
@@ -99,7 +99,6 @@ static void fuzz_palette_reset(TermWin *tw) {}
 static void fuzz_get_pos(TermWin *tw, int *x, int *y) { *x = *y = 0; }
 static void fuzz_get_pixels(TermWin *tw, int *x, int *y) { *x = *y = 0; }
 static const char *fuzz_get_title(TermWin *tw, bool icon) { return "moo"; }
-static bool fuzz_is_utf8(TermWin *tw) { return true; }
 
 static const TermWinVtable fuzz_termwin_vt = {
     .setup_draw_ctx = fuzz_setup_draw_ctx,
@@ -129,7 +128,6 @@ static const TermWinVtable fuzz_termwin_vt = {
     .get_pos = fuzz_get_pos,
     .get_pixels = fuzz_get_pixels,
     .get_title = fuzz_get_title,
-    .is_utf8 = fuzz_is_utf8,
 };
 
 void ldisc_send(Ldisc *ldisc, const void *buf, int len, bool interactive) {}
diff --git a/putty.h b/putty.h
index 8e8c5236..44aea084 100644
--- a/putty.h
+++ b/putty.h
@@ -1150,7 +1150,6 @@ struct TermWinVtable {
     void (*get_pos)(TermWin *, int *x, int *y);
     void (*get_pixels)(TermWin *, int *x, int *y);
     const char *(*get_title)(TermWin *, bool icon);
-    bool (*is_utf8)(TermWin *);
 };
 
 static inline bool win_setup_draw_ctx(TermWin *win)
@@ -1213,8 +1212,6 @@ static inline void win_get_pixels(TermWin *win, int *x, int *y)
 { win->vt->get_pixels(win, x, y); }
 static inline const char *win_get_title(TermWin *win, bool icon)
 { return win->vt->get_title(win, icon); }
-static inline bool win_is_utf8(TermWin *win)
-{ return win->vt->is_utf8(win); }
 
 /*
  * Global functions not specific to a connection instance.
diff --git a/terminal.c b/terminal.c
index d025a448..46d9bd16 100644
--- a/terminal.c
+++ b/terminal.c
@@ -7138,7 +7138,7 @@ char *term_get_ttymode(Terminal *term, const char *mode)
     if (strcmp(mode, "ERASE") == 0) {
         val = term->bksp_is_delete ? "^?" : "^H";
     } else if (strcmp(mode, "IUTF8") == 0) {
-        val = win_is_utf8(term->win) ? "yes" : "no";
+        val = (term->ucsdata->line_codepage == CP_UTF8) ? "yes" : "no";
     }
     /* FIXME: perhaps we should set ONLCR based on lfhascr as well? */
     /* FIXME: or ECHO and friends based on local echo state? */
diff --git a/unix/gtkwin.c b/unix/gtkwin.c
index b2196107..abc53fed 100644
--- a/unix/gtkwin.c
+++ b/unix/gtkwin.c
@@ -348,7 +348,7 @@ static int gtk_seat_get_userpass_input(Seat *seat, prompts_t *p,
 static bool gtk_seat_is_utf8(Seat *seat)
 {
     GtkFrontend *inst = container_of(seat, GtkFrontend, seat);
-    return win_is_utf8(&inst->termwin);
+    return inst->ucsdata.line_codepage == CS_UTF8;
 }
 
 static bool gtk_seat_get_window_pixel_size(Seat *seat, int *w, int *h)
@@ -4251,12 +4251,6 @@ static bool gtk_seat_get_windowid(Seat *seat, long *id)
 }
 #endif
 
-static bool gtkwin_is_utf8(TermWin *tw)
-{
-    GtkFrontend *inst = container_of(tw, GtkFrontend, termwin);
-    return inst->ucsdata.line_codepage == CS_UTF8;
-}
-
 char *setup_fonts_ucs(GtkFrontend *inst)
 {
     bool shadowbold = conf_get_bool(inst->conf, CONF_shadowbold);
@@ -5197,7 +5191,6 @@ static const TermWinVtable gtk_termwin_vt = {
     .get_pos = gtkwin_get_pos,
     .get_pixels = gtkwin_get_pixels,
     .get_title = gtkwin_get_title,
-    .is_utf8 = gtkwin_is_utf8,
 };
 
 void new_session_window(Conf *conf, const char *geometry_string)
diff --git a/windows/window.c b/windows/window.c
index cae0172d..e3c810ef 100644
--- a/windows/window.c
+++ b/windows/window.c
@@ -254,7 +254,6 @@ static void wintw_palette_reset(TermWin *);
 static void wintw_get_pos(TermWin *, int *x, int *y);
 static void wintw_get_pixels(TermWin *, int *x, int *y);
 static const char *wintw_get_title(TermWin *, bool icon);
-static bool wintw_is_utf8(TermWin *);
 
 static const TermWinVtable windows_termwin_vt = {
     .setup_draw_ctx = wintw_setup_draw_ctx,
@@ -284,7 +283,6 @@ static const TermWinVtable windows_termwin_vt = {
     .get_pos = wintw_get_pos,
     .get_pixels = wintw_get_pixels,
     .get_title = wintw_get_title,
-    .is_utf8 = wintw_is_utf8,
 };
 
 static TermWin wintw[1];
@@ -300,11 +298,6 @@ static bool is_utf8(void)
     return ucsdata.line_codepage == CP_UTF8;
 }
 
-static bool wintw_is_utf8(TermWin *tw)
-{
-    return is_utf8();
-}
-
 static bool win_seat_is_utf8(Seat *seat)
 {
     return is_utf8();