diff --git a/sys/dev/iwm/if_iwm_phy_ctxt.c b/sys/dev/iwm/if_iwm_phy_ctxt.c
index 5d8d7d24059..242e3abc388 100644
--- a/sys/dev/iwm/if_iwm_phy_ctxt.c
+++ b/sys/dev/iwm/if_iwm_phy_ctxt.c
@@ -218,6 +218,18 @@ iwm_mvm_phy_ctxt_cmd_data(struct iwm_softc *sc,
 	idle_cnt = chains_static;
 	active_cnt = chains_dynamic;
 
+	/* In scenarios where we only ever use a single-stream rates,
+	 * i.e. legacy 11b/g/a associations, single-stream APs or even
+	 * static SMPS, enable both chains to get diversity, improving
+	 * the case where we're far enough from the AP that attenuation
+	 * between the two antennas is sufficiently different to impact
+	 * performance.
+	 */
+	if (active_cnt == 1 && iwm_mvm_rx_diversity_allowed(sc)) {
+		idle_cnt = 2;
+		active_cnt = 2;
+	}
+
 	cmd->rxchain_info = htole32(iwm_mvm_get_valid_rx_ant(sc) <<
 					IWM_PHY_RX_CHAIN_VALID_POS);
 	cmd->rxchain_info |= htole32(idle_cnt << IWM_PHY_RX_CHAIN_CNT_POS);
diff --git a/sys/dev/iwm/if_iwm_util.c b/sys/dev/iwm/if_iwm_util.c
index 4ce9c8a6db5..4744fa16340 100644
--- a/sys/dev/iwm/if_iwm_util.c
+++ b/sys/dev/iwm/if_iwm_util.c
@@ -153,6 +153,7 @@ __FBSDID("$FreeBSD$");
 
 #include <dev/iwm/if_iwmreg.h>
 #include <dev/iwm/if_iwmvar.h>
+#include <dev/iwm/if_iwm_config.h>
 #include <dev/iwm/if_iwm_debug.h>
 #include <dev/iwm/if_iwm_binding.h>
 #include <dev/iwm/if_iwm_util.h>
@@ -487,3 +488,17 @@ iwm_dma_contig_free(struct iwm_dma_info *dma)
 		dma->tag = NULL;
 	}
 }
+
+boolean_t
+iwm_mvm_rx_diversity_allowed(struct iwm_softc *sc)
+{
+	if (num_of_ant(iwm_mvm_get_valid_rx_ant(sc)) == 1)
+		return FALSE;
+
+	/*
+	 * XXX Also return FALSE when SMPS (Spatial Multiplexing Powersave)
+	 *     is used on any vap (in the future).
+	 */
+
+	return TRUE;
+}
diff --git a/sys/dev/iwm/if_iwm_util.h b/sys/dev/iwm/if_iwm_util.h
index 460c660877c..f2109d4798a 100644
--- a/sys/dev/iwm/if_iwm_util.h
+++ b/sys/dev/iwm/if_iwm_util.h
@@ -120,6 +120,8 @@ extern	int iwm_dma_contig_alloc(bus_dma_tag_t tag, struct iwm_dma_info *dma,
 				 bus_size_t size, bus_size_t alignment);
 extern	void iwm_dma_contig_free(struct iwm_dma_info *);
 
+extern	boolean_t iwm_mvm_rx_diversity_allowed(struct iwm_softc *sc);
+
 extern	uint8_t iwm_ridx2rate(struct ieee80211_rateset *rs, int ridx);
 
 static inline uint8_t