--- a/src/gui_gtk_x11.c
+++ b/src/gui_gtk_x11.c
@@ -5316,6 +5316,62 @@ gui_mch_free_font(GuiFont font)
 }
 
 /*
+ * Cmdline expansion for setting 'guifont' / 'guifontwide'. Will enumerate
+ * through all fonts for completion. When setting 'guifont' it will only show
+ * monospace fonts as it's unlikely other fonts would be useful.
+ */
+    void
+gui_mch_expand_font(optexpand_T *args, void *param, int (*add_match)(char_u *val))
+{
+    PangoFontFamily	**font_families = NULL;
+    int			n_families = 0;
+    int			wide = *(int *)param;
+
+    if (args->oe_include_orig_val && *args->oe_opt_value == NUL && !wide)
+    {
+	// If guifont is empty, and we want to fill in the orig value, suggest
+	// the default so the user can modify it.
+	if (add_match((char_u *)DEFAULT_FONT) != OK)
+	    return;
+    }
+
+    pango_context_list_families(
+	    gui.text_context,
+	    &font_families,
+	    &n_families);
+
+    for (int i = 0; i < n_families; i++)
+    {
+	if (!wide && !pango_font_family_is_monospace(font_families[i]))
+	    continue;
+
+	const char* fam_name = pango_font_family_get_name(font_families[i]);
+	if (input_conv.vc_type != CONV_NONE)
+	{
+	    char_u *buf = string_convert(&input_conv, (char_u*)fam_name, NULL);
+	    if (buf != NULL)
+	    {
+		if (add_match(buf) != OK)
+		{
+		    vim_free(buf);
+		    break;
+		}
+		vim_free(buf);
+	    }
+	    else
+		break;
+	}
+	else
+	{
+	    if (add_match((char_u *)fam_name) != OK)
+		break;
+	}
+    }
+
+    g_free(font_families);
+}
+
+/*
  * Return the Pixel value (color) for the given color name.
  *
  * Return INVALCOLOR for error.

--- a/src/optiondefs.h
+++ b/src/optiondefs.h
@@ -1164,9 +1164,13 @@ static struct vimoption options[] =
 			    {(char_u *)NULL, (char_u *)0L}
 #endif
 			    SCTX_INIT},
-    {"guifont",	    "gfn",  P_STRING|P_VI_DEF|P_RCLR|P_ONECOMMA|P_NODUP,
+    {"guifont",	    "gfn",  P_STRING|P_VI_DEF|P_RCLR|P_ONECOMMA|P_NODUP
+#if !defined(FEAT_GUI_GTK)
+				|P_COLON
+#endif
+				,
 #ifdef FEAT_GUI
-			    (char_u *)&p_guifont, PV_NONE, did_set_guifont, NULL,
+			    (char_u *)&p_guifont, PV_NONE, did_set_guifont, expand_set_guifont,
 			    {(char_u *)"", (char_u *)0L}
 #else
 			    (char_u *)NULL, PV_NONE, NULL, NULL,
@@ -1183,10 +1187,14 @@ static struct vimoption options[] =
 			    {(char_u *)NULL, (char_u *)0L}
 #endif
 			    SCTX_INIT},
-    {"guifontwide", "gfw",  P_STRING|P_VI_DEF|P_RCLR|P_ONECOMMA|P_NODUP,
+    {"guifontwide", "gfw",  P_STRING|P_VI_DEF|P_RCLR|P_ONECOMMA|P_NODUP
+#if !defined(FEAT_GUI_GTK)
+				|P_COLON
+#endif
+				,
 #if defined(FEAT_GUI)
 			    (char_u *)&p_guifontwide, PV_NONE,
-			    did_set_guifontwide, NULL,
+			    did_set_guifontwide, expand_set_guifont,
 			    {(char_u *)"", (char_u *)0L}
 #else
 			    (char_u *)NULL, PV_NONE, NULL, NULL,

--- a/src/optionstr.c
+++ b/src/optionstr.c
@@ -731,7 +731,8 @@ did_set_option_listflag(char_u *val, cha
 }
 
 /*
- * Expand an option that accepts a list of string values.
+ * Expand an option that accepts a list of fixed string values with known
+ * number of items.
  */
     static int
 expand_set_opt_string(
@@ -801,10 +802,11 @@ static char_u *set_opt_callback_orig_opt
 static char_u *((*set_opt_callback_func)(expand_T *, int));
 
 /*
- * Callback used by expand_set_opt_generic to also include the original value.
+ * Callback used by expand_set_opt_generic to also include the original value
+ * as the first item.
  */
     static char_u *
-expand_set_opt_callback(expand_T *xp, int idx)
+expand_set_opt_generic_cb(expand_T *xp, int idx)
 {
     if (idx == 0)
     {
@@ -817,7 +819,8 @@ expand_set_opt_callback(expand_T *xp, in
 }
 
 /*
- * Expand an option with a callback that iterates through a list of possible names.
+ * Expand an option with a callback that iterates through a list of possible
+ * names using an index.
  */
     static int
 expand_set_opt_generic(
@@ -838,7 +841,7 @@ expand_set_opt_generic(
 	    args->oe_regmatch,
 	    matches,
 	    numMatches,
-	    expand_set_opt_callback,
+	    expand_set_opt_generic_cb,
 	    FALSE);
 
     set_opt_callback_orig_option = NULL;
@@ -846,6 +849,95 @@ expand_set_opt_generic(
     return ret;
 }
 
+static garray_T *expand_cb_ga;
+static optexpand_T *expand_cb_args;
+
+/*
+ * Callback provided to a function in expand_set_opt_callback. Will perform
+ * regex matching against the value and add to the list.
+ *
+ * Returns OK usually. Returns FAIL if it failed to allocate memory, and the
+ * caller should terminate the enumeration.
+ */
+    static int
+expand_set_opt_callback_cb(char_u *val)
+{
+    regmatch_T	*regmatch = expand_cb_args->oe_regmatch;
+    expand_T	*xp = expand_cb_args->oe_xp;
+    garray_T	*ga = expand_cb_ga;
+    char_u	*str;
+
+    if (val == NULL || *val == NUL)
+	return OK;
+
+    if (xp->xp_pattern[0] != NUL &&
+	    !vim_regexec(regmatch, val, (colnr_T)0))
+	return OK;
+
+    str = vim_strsave_escaped(val, (char_u *)" \t\\");
+
+    if (str == NULL)
+	return FAIL;
+
+    if (ga_grow(ga, 1) == FAIL)
+    {
+	vim_free(str);
+	return FAIL;
+    }
+
+    ((char_u **)ga->ga_data)[ga->ga_len] = str;
+    ++ga->ga_len;
+    return OK;
+}
+
+/*
+ * Expand an option with a provided function that takes a callback. The
+ * function will enumerate through all options and call the callback to add it
+ * to the list.
+ *
+ * "func" is the enumerator function that will generate the list of options.
+ * "func_params" is a single parameter that will be passed to func.
+ */
+    static int
+expand_set_opt_callback(
+	optexpand_T *args,
+	void (*func)(optexpand_T *, void* params, int (*cb)(char_u *val)),
+	void *func_params,
+	int *numMatches,
+	char_u ***matches)
+{
+    garray_T	ga;
+    int		include_orig_val = args->oe_include_orig_val;
+    char_u	*option_val = args->oe_opt_value;
+
+    ga_init2(&ga, sizeof(char *), 30);
+
+    if (include_orig_val && *option_val != NUL)
+    {
+	char_u *p = vim_strsave(option_val);
+	if (p == NULL)
+	    return FAIL;
+	if (ga_grow(&ga, 1) == FAIL)
+	{
+	    vim_free(p);
+	    return FAIL;
+	}
+	((char_u **)ga.ga_data)[ga.ga_len] = p;
+	++ga.ga_len;
+    }
+
+    expand_cb_ga = &ga;
+    expand_cb_args = args;
+
+    func(args, func_params, expand_set_opt_callback_cb);
+
+    expand_cb_ga = NULL;
+    expand_cb_args = NULL;
+
+    *matches = ga.ga_data;
+    *numMatches = ga.ga_len;
+    return OK;
+}
 
 /*
  * Expand an option which is a list of flags.
@@ -2237,6 +2329,27 @@ did_set_guifont(optset_T *args UNUSED)
     return errmsg;
 }
 
+/*
+ * Expand the 'guifont' option. Only when GUI is being used. Each platform has
+ * specific behaviors.
+ */
+    int
+expand_set_guifont(optexpand_T *args, int *numMatches, char_u ***matches)
+{
+    if (!gui.in_use)
+	return FAIL;
+
+# if defined(FEAT_GUI_MSWIN) || defined(FEAT_GUI_GTK)
+    char_u **varp = (char_u **)args->oe_varp;
+    int wide = (varp == &p_guifontwide);
+
+    return expand_set_opt_callback(
+	    args, gui_mch_expand_font, &wide, numMatches, matches);
+# else
+    return FAIL;
+# endif
+}
+
 # if defined(FEAT_XFONTSET) || defined(PROTO)
 /*
  * The 'guifontset' option is changed.

--- a/src/os_mswin.c
+++ b/src/os_mswin.c
@@ -2819,6 +2819,32 @@ points_to_pixels(WCHAR *str, WCHAR **end
     return pixels;
 }
 
+/*
+ * Convert pixel into point size. This is a reverse of points_to_pixels.
+ */
+    static double
+pixels_to_points(int pixels, int vertical, long_i pprinter_dc)
+{
+    double	points = 0;
+    HWND	hwnd = (HWND)0;
+    HDC		hdc;
+    HDC		printer_dc = (HDC)pprinter_dc;
+
+    if (printer_dc == NULL)
+    {
+	hwnd = GetDesktopWindow();
+	hdc = GetWindowDC(hwnd);
+    }
+    else
+	hdc = printer_dc;
+
+    points = pixels * 72.0 / GetDeviceCaps(hdc, vertical ? LOGPIXELSY : LOGPIXELSX);
+    if (printer_dc == NULL)
+	ReleaseDC(hwnd, hdc);
+
+    return points;
+}
+
     static int CALLBACK
 font_enumproc(
     ENUMLOGFONTW    *elf,
@@ -2890,6 +2916,100 @@ init_logfont(LOGFONTW *lf)
 }
 
 /*
+ * Call back for EnumFontFamiliesW in expand_font_enumproc.
+ *
+ */
+    static int CALLBACK
+expand_font_enumproc(
+    ENUMLOGFONTW    *elf,
+    NEWTEXTMETRICW  *ntm UNUSED,
+    DWORD	    type UNUSED,
+    LPARAM	    lparam)
+{
+    LOGFONTW *lf = (LOGFONTW*)elf;
+
+# ifndef FEAT_PROPORTIONAL_FONTS
+    // Ignore non-monospace fonts without further ado
+    if ((ntm->tmPitchAndFamily & 1) != 0)
+	return 1;
+# endif
+
+    // Filter only on ANSI. Otherwise will see a lot of random fonts that we
+    // usually don't want.
+    if (lf->lfCharSet != ANSI_CHARSET)
+        return 1;
+
+    int (*add_match)(char_u *) = (int (*)(char_u *))lparam;
+
+    WCHAR *faceNameW = lf->lfFaceName;
+    char_u *faceName = utf16_to_enc(faceNameW, NULL);
+    if (!faceName)
+	return 0;
+
+    add_match(faceName);
+    vim_free(faceName);
+
+    return 1;
+}
+
+/*
+ * Cmdline expansion for setting 'guifont'. Will enumerate through all
+ * monospace fonts for completion. If used after ':', will expand to possible
+ * font configuration options like font sizes.
+ *
+ * This function has "gui" in its name because in some platforms (GTK) font
+ * handling is done by the GUI code, whereas in Windows it's part of the
+ * platform code.
+ */
+    void
+gui_mch_expand_font(optexpand_T *args, void *param UNUSED, int (*add_match)(char_u *val))
+{
+    expand_T	    *xp = args->oe_xp;
+    if (xp->xp_pattern > args->oe_set_arg && *(xp->xp_pattern-1) == ':')
+    {
+	char buf[30];
+
+	// Always fill in with the current font size as first option for
+	// convenience. We simply round to the closest integer for simplicity.
+        int font_height = (int)round(
+		pixels_to_points(-current_font_height, TRUE, (long_i)NULL));
+	vim_snprintf(buf, ARRAY_LENGTH(buf), "h%d", font_height);
+	add_match((char_u *)buf);
+
+	// Note: Keep this in sync with get_logfont(). Don't include 'c' and
+	// 'q' as we fill in all the values below.
+	static char *(p_gfn_win_opt_values[]) = {
+	    "h" , "w" , "W" , "b" , "i" , "u" , "s"};
+	for (size_t i = 0; i < ARRAY_LENGTH(p_gfn_win_opt_values); i++)
+	    add_match((char_u *)p_gfn_win_opt_values[i]);
+
+	struct charset_pair *cp;
+	for (cp = charset_pairs; cp->name != NULL; ++cp)
+	{
+	    vim_snprintf(buf, ARRAY_LENGTH(buf), "c%s", cp->name);
+	    add_match((char_u *)buf);
+	}
+	struct quality_pair *qp;
+	for (qp = quality_pairs; qp->name != NULL; ++qp)
+	{
+	    vim_snprintf(buf, ARRAY_LENGTH(buf), "q%s", qp->name);
+	    add_match((char_u *)buf);
+	}
+	return;
+    }
+
+    HWND	hwnd = GetDesktopWindow();
+    HDC		hdc = GetWindowDC(hwnd);
+
+    EnumFontFamiliesW(hdc,
+	    NULL,
+	    (FONTENUMPROCW)expand_font_enumproc,
+	    (LPARAM)add_match);
+
+    ReleaseDC(hwnd, hdc);
+}
+
+/*
  * Compare a UTF-16 string and an ASCII string literally.
  * Only works all the code points are inside ASCII range.
  */
@@ -2995,6 +3115,7 @@ get_logfont(
     {
 	switch (*p++)
 	{
+	    // Note: Keep this in sync with gui_mch_expand_font().
 	    case L'h':
 		lf->lfHeight = - points_to_pixels(p, &p, TRUE, (long_i)printer_dc);
 		break;

--- a/src/proto/gui_gtk_x11.pro
+++ b/src/proto/gui_gtk_x11.pro
@@ -37,6 +37,7 @@ int gui_mch_init_font(char_u *font_name,
 GuiFont gui_mch_get_font(char_u *name, int report_error);
 char_u *gui_mch_get_fontname(GuiFont font, char_u *name);
 void gui_mch_free_font(GuiFont font);
+void gui_mch_expand_font(optexpand_T *args, void *param, int (*cb)(char_u *val));
 guicolor_T gui_mch_get_color(char_u *name);
 guicolor_T gui_mch_get_rgb_color(int r, int g, int b);
 void gui_mch_set_fg_color(guicolor_T color);

--- a/src/proto/optionstr.pro
+++ b/src/proto/optionstr.pro
@@ -152,6 +152,7 @@ int expand_set_foldclose(optexpand_T *ar
 int expand_set_foldmethod(optexpand_T *args, int *numMatches, char_u ***matches);
 int expand_set_foldopen(optexpand_T *args, int *numMatches, char_u ***matches);
 int expand_set_formatoptions(optexpand_T *args, int *numMatches, char_u ***matches);
+int expand_set_guifont(optexpand_T *args, int *numMatches, char_u ***matches);
 int expand_set_guioptions(optexpand_T *args, int *numMatches, char_u ***matches);
 int expand_set_highlight(optexpand_T *args, int *numMatches, char_u ***matches);
 int expand_set_jumpoptions(optexpand_T *args, int *numMatches, char_u ***matches);

--- a/src/proto/os_mswin.pro
+++ b/src/proto/os_mswin.pro
@@ -51,5 +51,6 @@ void serverProcessPendingMessages(void);
 char *charset_id2name(int id);
 char *quality_id2name(DWORD id);
 int get_logfont(LOGFONTW *lf, char_u *name, HDC printer_dc, int verbose);
+void gui_mch_expand_font(optexpand_T *args, void *param, int (*cb)(char_u *val));
 void channel_init_winsock(void);
 /* vim: set ft=c : */

--- a/src/testdir/test_gui.vim
+++ b/src/testdir/test_gui.vim
@@ -580,6 +580,56 @@ func Test_set_guifontwide()
   endif
 endfunc
 
+func Test_expand_guifont()
+  if has('gui_win32')
+    let guifont_saved = &guifont
+    let guifontwide_saved = &guifontwide
+
+    " Test recalling existing option, and suggesting current font size
+    set guifont=Courier\ New:h11:cANSI
+    call assert_equal('Courier\ New:h11:cANSI', getcompletion('set guifont=', 'cmdline')[0])
+    call assert_equal('h11', getcompletion('set guifont=Lucida\ Console:', 'cmdline')[0])
+
+    " Test auto-completion working for font names
+    call assert_equal(['Courier\ New'], getcompletion('set guifont=Couri*ew$', 'cmdline'))
+    call assert_equal(['Courier\ New'], getcompletion('set guifontwide=Couri*ew$', 'cmdline'))
+
+    " Make sure non-monospace fonts are filtered out
+    call assert_equal([], getcompletion('set guifont=Arial', 'cmdline'))
+    call assert_equal([], getcompletion('set guifontwide=Arial', 'cmdline'))
+
+    " Test auto-completion working for font options
+    call assert_notequal(-1, index(getcompletion('set guifont=Courier\ New:', 'cmdline'), 'b'))
+    call assert_equal(['cDEFAULT'], getcompletion('set guifont=Courier\ New:cD*T', 'cmdline'))
+    call assert_equal(['qCLEARTYPE'], getcompletion('set guifont=Courier\ New:qC*TYPE', 'cmdline'))
+
+    let &guifontwide = guifontwide_saved
+    let &guifont     = guifont_saved
+  elseif has('gui_gtk')
+    let guifont_saved = &guifont
+    let guifontwide_saved = &guifontwide
+
+    " Test recalling default and existing option
+    set guifont=
+    call assert_equal('Monospace\ 10', getcompletion('set guifont=', 'cmdline')[0])
+    set guifont=Monospace\ 9
+    call assert_equal('Monospace\ 9', getcompletion('set guifont=', 'cmdline')[0])
+
+    " Test auto-completion working for font names
+    call assert_equal(['Monospace'], getcompletion('set guifont=Mono*pace$', 'cmdline'))
+    call assert_equal(['Monospace'], getcompletion('set guifontwide=Mono*pace$', 'cmdline'))
+
+    " Make sure non-monospace fonts are filtered out only in 'guifont'
+    call assert_equal([], getcompletion('set guifont=Sans$', 'cmdline'))
+    call assert_equal(['Sans'], getcompletion('set guifontwide=Sans$', 'cmdline'))
+
+    let &guifontwide = guifontwide_saved
+    let &guifont     = guifont_saved
+  else
+    call assert_equal([], getcompletion('set guifont=', 'cmdline'))
+  endif
+endfunc
+
 func Test_set_guiligatures()
   CheckX11BasedGui
 

--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1991,
+/**/
     1990,
 /**/
     1989,