diff --git a/config.c b/config.c
index 26d2d1a0..431d7817 100644
--- a/config.c
+++ b/config.c
@@ -360,7 +360,7 @@ parse_section_main(const char *key, const char *value, struct config *conf,
     else if (strcmp(key, "scrollback") == 0) {
         LOG_WARN("deprecated: [default]: scrollback: use 'scrollback.lines' instead'");
 
-        const char *fmt = "%s:%d: \e[1mdefault.scrollback\e[21m, use \e[1mscrollback.lines\e[21m instead";
+        const char *fmt = "%s:%d: \033[1mdefault.scrollback\033[21m, use \033[1mscrollback.lines\033[21m instead";
         int len = snprintf(NULL, 0, fmt, path, lineno);
         char *text = malloc(len + 1);
         snprintf(text, len + 1, fmt, path, lineno);
diff --git a/log.c b/log.c
index c5d90937..23d4b197 100644
--- a/log.c
+++ b/log.c
@@ -60,14 +60,14 @@ _log(enum log_class log_class, const char *module, const char *file, int lineno,
     }
 
     char clr[16];
-    snprintf(clr, sizeof(clr), "\e[%dm", class_clr);
-    fprintf(stderr, "%s%s%s: ", colorize ? clr : "", class, colorize ? "\e[0m" : "");
+    snprintf(clr, sizeof(clr), "\033[%dm", class_clr);
+    fprintf(stderr, "%s%s%s: ", colorize ? clr : "", class, colorize ? "\033[0m" : "");
 
     if (colorize)
-        fprintf(stderr, "\e[2m");
+        fprintf(stderr, "\033[2m");
     fprintf(stderr, "%s:%d: ", file, lineno);
     if (colorize)
-        fprintf(stderr, "\e[0m");
+        fprintf(stderr, "\033[0m");
 
     vfprintf(stderr, fmt, va);
 
diff --git a/osc.c b/osc.c
index 42bef722..39a9cb6f 100644
--- a/osc.c
+++ b/osc.c
@@ -575,7 +575,7 @@ osc_dispatch(struct terminal *term)
 
             /*
              * Reply in XParseColor format
-             * E.g. for color 0xdcdccc we reply "\e]10;rgb:dc/dc/cc\e\\"
+             * E.g. for color 0xdcdccc we reply "\033]10;rgb:dc/dc/cc\033\\"
              */
             char reply[32];
             snprintf(
diff --git a/slave.c b/slave.c
index ed0f94be..cb6a2f27 100644
--- a/slave.c
+++ b/slave.c
@@ -73,19 +73,19 @@ static enum user_notification_ret_t
 emit_one_notification(int fd, const struct user_notification *notif)
 {
     const char *prefix = NULL;
-    const char *postfix = "\e[m\n";
+    const char *postfix = "\033[m\n";
 
     switch (notif->kind) {
     case USER_NOTIFICATION_DEPRECATED:
-        prefix = "\e[33;1mdeprecated\e[39;21m: ";
+        prefix = "\033[33;1mdeprecated\033[39;21m: ";
         break;
 
     case USER_NOTIFICATION_WARNING:
-        prefix = "\e[33;1mwarning\e[39;21m: ";
+        prefix = "\033[33;1mwarning\033[39;21m: ";
         break;
 
     case USER_NOTIFICATION_ERROR:
-        prefix = "\e[31;1merror\e[39;21m: ";
+        prefix = "\033[31;1merror\033[39;21m: ";
         break;
     }