diff --git a/hostapd/config_file.c b/hostapd/config_file.c
index e3cad7c9f..3466f2851 100644
--- a/hostapd/config_file.c
+++ b/hostapd/config_file.c
@@ -1856,6 +1856,48 @@ static struct wpabuf * hostapd_parse_bin(const char *buf)
 #endif /* CONFIG_WPS_NFC */
 
 
+#ifdef CONFIG_ACS
+static int hostapd_config_parse_acs_chan_bias(struct hostapd_config *conf,
+					      char *pos)
+{
+	struct acs_bias *bias = NULL, *tmp;
+	unsigned int num = 0;
+	char *end;
+
+	while (*pos) {
+		tmp = os_realloc_array(bias, num + 1, sizeof(*bias));
+		if (!tmp)
+			goto fail;
+		bias = tmp;
+
+		bias[num].channel = atoi(pos);
+		if (bias[num].channel <= 0)
+			goto fail;
+		pos = os_strchr(pos, ':');
+		if (!pos)
+			goto fail;
+		pos++;
+		bias[num].bias = strtod(pos, &end);
+		if (end == pos || bias[num].bias < 0.0)
+			goto fail;
+		pos = end;
+		if (*pos != ' ' && *pos != '\0')
+			goto fail;
+		num++;
+	}
+
+	os_free(conf->acs_chan_bias);
+	conf->acs_chan_bias = bias;
+	conf->num_acs_chan_bias = num;
+
+	return 0;
+fail:
+	os_free(bias);
+	return -1;
+}
+#endif /* CONFIG_ACS */
+
+
 static int hostapd_config_fill(struct hostapd_config *conf,
 			       struct hostapd_bss_config *bss,
 			       char *buf, char *pos, int line)
@@ -2508,6 +2550,12 @@ static int hostapd_config_fill(struct hostapd_config *conf,
 			return 1;
 		}
 		conf->acs_num_scans = val;
+	} else if (os_strcmp(buf, "acs_chan_bias") == 0) {
+		if (hostapd_config_parse_acs_chan_bias(conf, pos)) {
+			wpa_printf(MSG_ERROR, "Line %d: invalid acs_chan_bias",
+				   line);
+			return -1;
+		}
 #endif /* CONFIG_ACS */
 	} else if (os_strcmp(buf, "dtim_period") == 0) {
 		bss->dtim_period = atoi(pos);
diff --git a/hostapd/hostapd.conf b/hostapd/hostapd.conf
index 1e5695984..dd05c2ffd 100644
--- a/hostapd/hostapd.conf
+++ b/hostapd/hostapd.conf
@@ -154,8 +154,19 @@ channel=1
 # interference that may help choosing a better channel. This can also help fine
 # tune the ACS scan time in case a driver has different scan dwell times.
 #
+# acs_chan_bias is a space-separated list of <channel>:<bias> pairs. It can be
+# used to increase (or decrease) the likelihood of a specific channel to be
+# selected by the ACS algorithm. The total interference factor for each channel
+# gets multiplied by the specified bias value before finding the channel with
+# the lowest value. In other words, values between 0.0 and 1.0 can be used to
+# make a channel more likely to be picked while values larger than 1.0 make the
+# specified channel less likely to be picked. This can be used, e.g., to prefer
+# the commonly used 2.4 GHz band channels 1, 6, and 11 (which is the default
+# behavior on 2.4 GHz band if no acs_chan_bias parameter is specified).
+#
 # Defaults:
 #acs_num_scans=5
+#acs_chan_bias=1:0.8 6:0.8 11:0.8
 
 # Channel list restriction. This option allows hostapd to select one of the
 # provided channels when a channel should be automatically selected.
diff --git a/src/ap/acs.c b/src/ap/acs.c
index 78fd949af..15a474164 100644
--- a/src/ap/acs.c
+++ b/src/ap/acs.c
@@ -517,6 +517,19 @@ static struct hostapd_channel_data *acs_find_chan(struct hostapd_iface *iface,
 }
 
 
+static int is_24ghz_mode(enum hostapd_hw_mode mode)
+{
+	return mode == HOSTAPD_MODE_IEEE80211B ||
+		mode == HOSTAPD_MODE_IEEE80211G;
+}
+
+
+static int is_common_24ghz_chan(int chan)
+{
+	return chan == 1 || chan == 6 || chan == 11;
+}
+
+
 #ifndef ACS_ADJ_WEIGHT
 #define ACS_ADJ_WEIGHT 0.85
 #endif /* ACS_ADJ_WEIGHT */
@@ -525,6 +538,15 @@ static struct hostapd_channel_data *acs_find_chan(struct hostapd_iface *iface,
 #define ACS_NEXT_ADJ_WEIGHT 0.55
 #endif /* ACS_NEXT_ADJ_WEIGHT */
 
+#ifndef ACS_24GHZ_PREFER_1_6_11
+/*
+ * Select commonly used channels 1, 6, 11 by default even if a neighboring
+ * channel has a smaller interference factor as long as it is not better by more
+ * than this multiplier.
+ */
+#define ACS_24GHZ_PREFER_1_6_11 0.8
+#endif /* ACS_24GHZ_PREFER_1_6_11 */
+
 /*
  * At this point it's assumed chan->interface_factor has been computed.
  * This function should be reusable regardless of interference computation
@@ -539,6 +561,7 @@ acs_find_ideal_chan(struct hostapd_iface *iface)
 	long double factor, ideal_factor = 0;
 	int i, j;
 	int n_chans = 1;
+	unsigned int k;
 
 	/* TODO: HT40- support */
 
@@ -566,6 +589,7 @@ acs_find_ideal_chan(struct hostapd_iface *iface)
 
 	for (i = 0; i < iface->current_mode->num_channels; i++) {
 		double total_weight;
+		struct acs_bias *bias, tmp_bias;
 
 		chan = &iface->current_mode->channels[i];
 
@@ -619,8 +643,7 @@ acs_find_ideal_chan(struct hostapd_iface *iface)
 
 		/* 2.4 GHz has overlapping 20 MHz channels. Include adjacent
 		 * channel interference factor. */
-		if (iface->current_mode->mode == HOSTAPD_MODE_IEEE80211B ||
-		    iface->current_mode->mode == HOSTAPD_MODE_IEEE80211G) {
+		if (is_24ghz_mode(iface->current_mode->mode)) {
 			for (j = 0; j < n_chans; j++) {
 				adj_chan = acs_find_chan(iface, chan->freq +
 							 (j * 20) - 5);
@@ -658,8 +681,31 @@ acs_find_ideal_chan(struct hostapd_iface *iface)
 
 		factor /= total_weight;
 
-		wpa_printf(MSG_DEBUG, "ACS:  * channel %d: total interference = %Lg",
-			   chan->chan, factor);
+		bias = NULL;
+		if (iface->conf->acs_chan_bias) {
+			for (k = 0; k < iface->conf->num_acs_chan_bias; k++) {
+				bias = &iface->conf->acs_chan_bias[k];
+				if (bias->channel == chan->chan)
+					break;
+				bias = NULL;
+			}
+		} else if (is_24ghz_mode(iface->current_mode->mode) &&
+			   is_common_24ghz_chan(chan->chan)) {
+			tmp_bias.channel = chan->chan;
+			tmp_bias.bias = ACS_24GHZ_PREFER_1_6_11;
+			bias = &tmp_bias;
+		}
+
+		if (bias) {
+			factor *= bias->bias;
+			wpa_printf(MSG_DEBUG,
+				   "ACS:  * channel %d: total interference = %Lg (%f bias)",
+				   chan->chan, factor, bias->bias);
+		} else {
+			wpa_printf(MSG_DEBUG,
+				   "ACS:  * channel %d: total interference = %Lg",
+				   chan->chan, factor);
+		}
 
 		if (acs_usable_chan(chan) &&
 		    (!ideal_chan || factor < ideal_factor)) {
diff --git a/src/ap/ap_config.c b/src/ap/ap_config.c
index 1c0ed7aa9..c1861d4f7 100644
--- a/src/ap/ap_config.c
+++ b/src/ap/ap_config.c
@@ -574,6 +574,9 @@ void hostapd_config_free(struct hostapd_config *conf)
 	os_free(conf->basic_rates);
 	os_free(conf->chanlist);
 	os_free(conf->driver_params);
+#ifdef CONFIG_ACS
+	os_free(conf->acs_chan_bias);
+#endif /* CONFIG_ACS */
 
 	os_free(conf);
 }
diff --git a/src/ap/ap_config.h b/src/ap/ap_config.h
index e5215c529..0f33ac9a0 100644
--- a/src/ap/ap_config.h
+++ b/src/ap/ap_config.h
@@ -639,6 +639,11 @@ struct hostapd_config {
 
 #ifdef CONFIG_ACS
 	unsigned int acs_num_scans;
+	struct acs_bias {
+		int channel;
+		double bias;
+	} *acs_chan_bias;
+	unsigned int num_acs_chan_bias;
 #endif /* CONFIG_ACS */
 };