diff --git a/core/embed/extmod/modtrezorio/modtrezorio-hid.h b/core/embed/extmod/modtrezorio/modtrezorio-hid.h
index 532dc8ce5..4a13c4013 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-hid.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-hid.h
@@ -33,6 +33,7 @@ typedef struct _mp_obj_HID_t {
 ///     iface_num: int,
 ///     ep_in: int,
 ///     ep_out: int,
+///     emu_port: int,
 ///     report_desc: bytes,
 ///     subclass: int = 0,
 ///     protocol: int = 0,
@@ -54,6 +55,9 @@ STATIC mp_obj_t mod_trezorio_HID_make_new(const mp_obj_type_t *type,
       {MP_QSTR_ep_out,
        MP_ARG_REQUIRED | MP_ARG_KW_ONLY | MP_ARG_INT,
        {.u_int = 0}},
+      {MP_QSTR_emu_port,
+       MP_ARG_REQUIRED | MP_ARG_KW_ONLY | MP_ARG_INT,
+       {.u_int = 0}},
       {MP_QSTR_subclass, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0}},
       {MP_QSTR_protocol, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0}},
       {MP_QSTR_polling_interval, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1}},
@@ -69,12 +73,13 @@ STATIC mp_obj_t mod_trezorio_HID_make_new(const mp_obj_type_t *type,
   const mp_int_t iface_num = vals[0].u_int;
   const mp_int_t ep_in = vals[1].u_int;
   const mp_int_t ep_out = vals[2].u_int;
-  const mp_int_t subclass = vals[3].u_int;
-  const mp_int_t protocol = vals[4].u_int;
-  const mp_int_t polling_interval = vals[5].u_int;
-  const mp_int_t max_packet_len = vals[6].u_int;
+  const mp_int_t emu_port = vals[3].u_int;
+  const mp_int_t subclass = vals[4].u_int;
+  const mp_int_t protocol = vals[5].u_int;
+  const mp_int_t polling_interval = vals[6].u_int;
+  const mp_int_t max_packet_len = vals[7].u_int;
   mp_buffer_info_t report_desc = {0};
-  mp_get_buffer_raise(vals[7].u_obj, &report_desc, MP_BUFFER_READ);
+  mp_get_buffer_raise(vals[8].u_obj, &report_desc, MP_BUFFER_READ);
 
   if (report_desc.buf == NULL || report_desc.len == 0 ||
       report_desc.len > 255) {
@@ -83,6 +88,7 @@ STATIC mp_obj_t mod_trezorio_HID_make_new(const mp_obj_type_t *type,
   CHECK_PARAM_RANGE(iface_num, 0, 32)
   CHECK_PARAM_RANGE(ep_in, 0, 255)
   CHECK_PARAM_RANGE(ep_out, 0, 255)
+  CHECK_PARAM_RANGE(emu_port, 0, 65535)
   CHECK_PARAM_RANGE(subclass, 0, 255)
   CHECK_PARAM_RANGE(protocol, 0, 255)
   CHECK_PARAM_RANGE(polling_interval, 1, 255)
@@ -94,8 +100,12 @@ STATIC mp_obj_t mod_trezorio_HID_make_new(const mp_obj_type_t *type,
   o->info.rx_buffer = m_new(uint8_t, max_packet_len);
   o->info.report_desc = report_desc.buf;
   o->info.iface_num = (uint8_t)(iface_num);
+#ifdef TREZOR_EMULATOR
+  o->info.emu_port = (uint16_t)(emu_port);
+#else
   o->info.ep_in = (uint8_t)(ep_in);
   o->info.ep_out = (uint8_t)(ep_out);
+#endif
   o->info.subclass = (uint8_t)(subclass);
   o->info.protocol = (uint8_t)(protocol);
   o->info.polling_interval = (uint8_t)(polling_interval);
diff --git a/core/embed/extmod/modtrezorio/modtrezorio-vcp.h b/core/embed/extmod/modtrezorio/modtrezorio-vcp.h
index 6a427c041..47160a569 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-vcp.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-vcp.h
@@ -37,6 +37,7 @@ typedef struct _mp_obj_VCP_t {
 ///     ep_in: int,
 ///     ep_out: int,
 ///     ep_cmd: int,
+///     emu_port: int,
 /// ) -> None:
 ///     """
 ///     """
@@ -59,6 +60,9 @@ STATIC mp_obj_t mod_trezorio_VCP_make_new(const mp_obj_type_t *type,
       {MP_QSTR_ep_cmd,
        MP_ARG_REQUIRED | MP_ARG_KW_ONLY | MP_ARG_INT,
        {.u_int = 0}},
+      {MP_QSTR_emu_port,
+       MP_ARG_REQUIRED | MP_ARG_KW_ONLY | MP_ARG_INT,
+       {.u_int = 0}},
   };
   mp_arg_val_t vals[MP_ARRAY_SIZE(allowed_args)] = {0};
   mp_arg_parse_all_kw_array(n_args, n_kw, args, MP_ARRAY_SIZE(allowed_args),
@@ -69,12 +73,14 @@ STATIC mp_obj_t mod_trezorio_VCP_make_new(const mp_obj_type_t *type,
   const mp_int_t ep_in = vals[2].u_int;
   const mp_int_t ep_out = vals[3].u_int;
   const mp_int_t ep_cmd = vals[4].u_int;
+  const mp_int_t emu_port = vals[5].u_int;
 
   CHECK_PARAM_RANGE(iface_num, 0, 32)
   CHECK_PARAM_RANGE(data_iface_num, 0, 32)
   CHECK_PARAM_RANGE(ep_in, 0, 255)
   CHECK_PARAM_RANGE(ep_out, 0, 255)
   CHECK_PARAM_RANGE(ep_cmd, 0, 255)
+  CHECK_PARAM_RANGE(emu_port, 0, 65535)
 
   const size_t vcp_buffer_len = 1024;
   const size_t vcp_packet_len = 64;
@@ -92,9 +98,13 @@ STATIC mp_obj_t mod_trezorio_VCP_make_new(const mp_obj_type_t *type,
   o->info.rx_intr_byte = 3;  // Ctrl-C
   o->info.iface_num = (uint8_t)(iface_num);
   o->info.data_iface_num = (uint8_t)(data_iface_num);
+#ifdef TREZOR_EMULATOR
+  o->info.emu_port = (uint16_t)(emu_port);
+#else
   o->info.ep_cmd = (uint8_t)(ep_cmd);
   o->info.ep_in = (uint8_t)(ep_in);
   o->info.ep_out = (uint8_t)(ep_out);
+#endif
   o->info.polling_interval = 10;
   o->info.max_packet_len = (uint8_t)(vcp_packet_len);
 
diff --git a/core/embed/extmod/modtrezorio/modtrezorio-webusb.h b/core/embed/extmod/modtrezorio/modtrezorio-webusb.h
index e18ba38cf..b56be1bd5 100644
--- a/core/embed/extmod/modtrezorio/modtrezorio-webusb.h
+++ b/core/embed/extmod/modtrezorio/modtrezorio-webusb.h
@@ -33,6 +33,7 @@ typedef struct _mp_obj_WebUSB_t {
 ///     iface_num: int,
 ///     ep_in: int,
 ///     ep_out: int,
+///     emu_port: int,
 ///     subclass: int = 0,
 ///     protocol: int = 0,
 ///     polling_interval: int = 1,
@@ -53,6 +54,9 @@ STATIC mp_obj_t mod_trezorio_WebUSB_make_new(const mp_obj_type_t *type,
       {MP_QSTR_ep_out,
        MP_ARG_REQUIRED | MP_ARG_KW_ONLY | MP_ARG_INT,
        {.u_int = 0}},
+      {MP_QSTR_emu_port,
+       MP_ARG_REQUIRED | MP_ARG_KW_ONLY | MP_ARG_INT,
+       {.u_int = 0}},
       {MP_QSTR_subclass, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0}},
       {MP_QSTR_protocol, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0}},
       {MP_QSTR_polling_interval, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 1}},
@@ -65,14 +69,16 @@ STATIC mp_obj_t mod_trezorio_WebUSB_make_new(const mp_obj_type_t *type,
   const mp_int_t iface_num = vals[0].u_int;
   const mp_int_t ep_in = vals[1].u_int;
   const mp_int_t ep_out = vals[2].u_int;
-  const mp_int_t subclass = vals[3].u_int;
-  const mp_int_t protocol = vals[4].u_int;
-  const mp_int_t polling_interval = vals[5].u_int;
-  const mp_int_t max_packet_len = vals[6].u_int;
+  const mp_int_t emu_port = vals[3].u_int;
+  const mp_int_t subclass = vals[4].u_int;
+  const mp_int_t protocol = vals[5].u_int;
+  const mp_int_t polling_interval = vals[6].u_int;
+  const mp_int_t max_packet_len = vals[7].u_int;
 
   CHECK_PARAM_RANGE(iface_num, 0, 32)
   CHECK_PARAM_RANGE(ep_in, 0, 255)
   CHECK_PARAM_RANGE(ep_out, 0, 255)
+  CHECK_PARAM_RANGE(emu_port, 0, 65535)
   CHECK_PARAM_RANGE(subclass, 0, 255)
   CHECK_PARAM_RANGE(protocol, 0, 255)
   CHECK_PARAM_RANGE(polling_interval, 1, 255)
@@ -83,8 +89,12 @@ STATIC mp_obj_t mod_trezorio_WebUSB_make_new(const mp_obj_type_t *type,
 
   o->info.rx_buffer = m_new(uint8_t, max_packet_len);
   o->info.iface_num = (uint8_t)(iface_num);
+#ifdef TREZOR_EMULATOR
+  o->info.emu_port = (uint16_t)(emu_port);
+#else
   o->info.ep_in = (uint8_t)(ep_in);
   o->info.ep_out = (uint8_t)(ep_out);
+#endif
   o->info.subclass = (uint8_t)(subclass);
   o->info.protocol = (uint8_t)(protocol);
   o->info.polling_interval = (uint8_t)(polling_interval);
diff --git a/core/embed/trezorhal/usb_hid-defs.h b/core/embed/trezorhal/usb_hid-defs.h
index d83c06381..9062d71eb 100644
--- a/core/embed/trezorhal/usb_hid-defs.h
+++ b/core/embed/trezorhal/usb_hid-defs.h
@@ -41,10 +41,14 @@ typedef struct {
   const uint8_t *report_desc;  // With length of report_desc_len bytes
   uint8_t *rx_buffer;          // With length of max_packet_len bytes
   uint8_t iface_num;           // Address of this HID interface
-  uint8_t ep_in;     // Address of IN endpoint (with the highest bit set)
-  uint8_t ep_out;    // Address of OUT endpoint
-  uint8_t subclass;  // usb_iface_subclass_t
-  uint8_t protocol;  // usb_iface_protocol_t
+#ifdef TREZOR_EMULATOR
+  uint16_t emu_port;  // UDP port of this interface in the emulator.
+#else
+  uint8_t ep_in;   // Address of IN endpoint (with the highest bit set)
+  uint8_t ep_out;  // Address of OUT endpoint
+#endif
+  uint8_t subclass;          // usb_iface_subclass_t
+  uint8_t protocol;          // usb_iface_protocol_t
   uint8_t polling_interval;  // In units of 1ms
   uint8_t max_packet_len;    // Length of the biggest report and of rx_buffer
   uint8_t report_desc_len;   // Length of report_desc
diff --git a/core/embed/trezorhal/usb_vcp-defs.h b/core/embed/trezorhal/usb_vcp-defs.h
index 67656a793..849aed06f 100644
--- a/core/embed/trezorhal/usb_vcp-defs.h
+++ b/core/embed/trezorhal/usb_vcp-defs.h
@@ -105,9 +105,13 @@ typedef struct {
   uint8_t iface_num;         // Address of this VCP interface
   uint8_t data_iface_num;    // Address of data interface of the VCP interface
                              // association
+#ifdef TREZOR_EMULATOR
+  uint16_t emu_port;  // UDP port of this interface in the emulator.
+#else
   uint8_t ep_cmd;  // Address of IN CMD endpoint (with the highest bit set)
   uint8_t ep_in;   // Address of IN endpoint (with the highest bit set)
   uint8_t ep_out;  // Address of OUT endpoint
+#endif
   uint8_t polling_interval;  // In units of 1ms
   uint8_t max_packet_len;  // Length of the biggest packet, and of tx_packet and
                            // rx_packet
diff --git a/core/embed/trezorhal/usb_webusb-defs.h b/core/embed/trezorhal/usb_webusb-defs.h
index 046f803cc..aa475bf36 100644
--- a/core/embed/trezorhal/usb_webusb-defs.h
+++ b/core/embed/trezorhal/usb_webusb-defs.h
@@ -32,10 +32,14 @@ typedef struct __attribute__((packed)) {
 typedef struct {
   uint8_t *rx_buffer;  // With length of max_packet_len bytes
   uint8_t iface_num;   // Address of this WebUSB interface
-  uint8_t ep_in;       // Address of IN endpoint (with the highest bit set)
-  uint8_t ep_out;      // Address of OUT endpoint
-  uint8_t subclass;    // usb_iface_subclass_t
-  uint8_t protocol;    // usb_iface_protocol_t
+#ifdef TREZOR_EMULATOR
+  uint16_t emu_port;  // UDP port of this interface in the emulator.
+#else
+  uint8_t ep_in;   // Address of IN endpoint (with the highest bit set)
+  uint8_t ep_out;  // Address of OUT endpoint
+#endif
+  uint8_t subclass;          // usb_iface_subclass_t
+  uint8_t protocol;          // usb_iface_protocol_t
   uint8_t polling_interval;  // In units of 1ms
   uint8_t max_packet_len;    // Length of the biggest report and of rx_buffer
 } usb_webusb_info_t;
diff --git a/core/embed/unix/usb.c b/core/embed/unix/usb.c
index 1a439a594..db7b8d389 100644
--- a/core/embed/unix/usb.c
+++ b/core/embed/unix/usb.c
@@ -49,6 +49,7 @@ __fatal_error(const char *expr, const char *msg, const char *file, int line,
 
 static struct {
   usb_iface_type_t type;
+  uint16_t port;
   int sock;
   struct sockaddr_in si_me, si_other;
   socklen_t slen;
@@ -58,6 +59,7 @@ void usb_init(const usb_dev_info_t *dev_info) {
   (void)dev_info;
   for (int i = 0; i < USBD_MAX_NUM_INTERFACES; i++) {
     usb_ifaces[i].type = USB_IFACE_TYPE_DISABLED;
+    usb_ifaces[i].port = 0;
     usb_ifaces[i].sock = -1;
     memzero(&usb_ifaces[i].si_me, sizeof(struct sockaddr_in));
     memzero(&usb_ifaces[i].si_other, sizeof(struct sockaddr_in));
@@ -69,7 +71,6 @@ void usb_deinit(void) {}
 
 void usb_start(void) {
   const char *ip = getenv("TREZOR_UDP_IP");
-  const char *port = getenv("TREZOR_UDP_PORT");
 
   // iterate interfaces
   for (int i = 0; i < USBD_MAX_NUM_INTERFACES; i++) {
@@ -90,11 +91,7 @@ void usb_start(void) {
     } else {
       usb_ifaces[i].si_me.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
     }
-    if (port) {
-      usb_ifaces[i].si_me.sin_port = htons(atoi(port) + i);
-    } else {
-      usb_ifaces[i].si_me.sin_port = htons(TREZOR_UDP_PORT + i);
-    }
+    usb_ifaces[i].si_me.sin_port = htons(usb_ifaces[i].port);
 
     ensure(sectrue * (0 == bind(usb_ifaces[i].sock,
                                 (struct sockaddr *)&usb_ifaces[i].si_me,
@@ -109,6 +106,7 @@ secbool usb_hid_add(const usb_hid_info_t *info) {
   if (info->iface_num < USBD_MAX_NUM_INTERFACES &&
       usb_ifaces[info->iface_num].type == USB_IFACE_TYPE_DISABLED) {
     usb_ifaces[info->iface_num].type = USB_IFACE_TYPE_HID;
+    usb_ifaces[info->iface_num].port = info->emu_port;
   }
   return sectrue;
 }
@@ -117,6 +115,7 @@ secbool usb_webusb_add(const usb_webusb_info_t *info) {
   if (info->iface_num < USBD_MAX_NUM_INTERFACES &&
       usb_ifaces[info->iface_num].type == USB_IFACE_TYPE_DISABLED) {
     usb_ifaces[info->iface_num].type = USB_IFACE_TYPE_WEBUSB;
+    usb_ifaces[info->iface_num].port = info->emu_port;
   }
   return sectrue;
 }
@@ -125,6 +124,7 @@ secbool usb_vcp_add(const usb_vcp_info_t *info) {
   if (info->iface_num < USBD_MAX_NUM_INTERFACES &&
       usb_ifaces[info->iface_num].type == USB_IFACE_TYPE_DISABLED) {
     usb_ifaces[info->iface_num].type = USB_IFACE_TYPE_VCP;
+    usb_ifaces[info->iface_num].port = info->emu_port;
   }
   return sectrue;
 }
diff --git a/core/mocks/generated/trezorio/__init__.pyi b/core/mocks/generated/trezorio/__init__.pyi
index 0fc6bdaf9..e9fa19038 100644
--- a/core/mocks/generated/trezorio/__init__.pyi
+++ b/core/mocks/generated/trezorio/__init__.pyi
@@ -42,6 +42,7 @@ class HID:
         iface_num: int,
         ep_in: int,
         ep_out: int,
+        emu_port: int,
         report_desc: bytes,
         subclass: int = 0,
         protocol: int = 0,
@@ -148,6 +149,7 @@ class VCP:
         ep_in: int,
         ep_out: int,
         ep_cmd: int,
+        emu_port: int,
     ) -> None:
         """
         """
@@ -169,6 +171,7 @@ class WebUSB:
         iface_num: int,
         ep_in: int,
         ep_out: int,
+        emu_port: int,
         subclass: int = 0,
         protocol: int = 0,
         polling_interval: int = 1,
diff --git a/core/src/usb.py b/core/src/usb.py
index cb732e618..c232bbd27 100644
--- a/core/src/usb.py
+++ b/core/src/usb.py
@@ -1,6 +1,19 @@
+from micropython import const
+
 from storage.device import get_device_id
 from trezor import io, utils
 
+UDP_PORT = 0
+WIRE_PORT_OFFSET = const(0)
+DEBUGLINK_PORT_OFFSET = const(1)
+WEBAUTHN_PORT_OFFSET = const(2)
+VCP_PORT_OFFSET = const(3)
+
+if utils.EMULATOR:
+    import uos
+
+    UDP_PORT = int(uos.getenv("TREZOR_UDP_PORT") or "21324")
+
 _iface_iter = iter(range(5))
 
 ENABLE_IFACE_DEBUG = __debug__
@@ -23,6 +36,7 @@ iface_wire = io.WebUSB(
     iface_num=id_wire,
     ep_in=0x81 + id_wire,
     ep_out=0x01 + id_wire,
+    emu_port=UDP_PORT + WIRE_PORT_OFFSET,
 )
 
 # XXXXXXXXXXXXXXXXXXX
@@ -43,6 +57,7 @@ if __debug__ and ENABLE_IFACE_DEBUG:
         iface_num=id_debug,
         ep_in=0x81 + id_debug,
         ep_out=0x01 + id_debug,
+        emu_port=UDP_PORT + DEBUGLINK_PORT_OFFSET,
     )
 
 if not utils.BITCOIN_ONLY and ENABLE_IFACE_WEBAUTHN:
@@ -52,6 +67,7 @@ if not utils.BITCOIN_ONLY and ENABLE_IFACE_WEBAUTHN:
         iface_num=id_webauthn,
         ep_in=0x81 + id_webauthn,
         ep_out=0x01 + id_webauthn,
+        emu_port=UDP_PORT + WEBAUTHN_PORT_OFFSET,
         # fmt: off
         report_desc=bytes([
             0x06, 0xd0, 0xf1,  # USAGE_PAGE (FIDO Alliance)
@@ -84,6 +100,7 @@ if __debug__ and ENABLE_IFACE_VCP:
         ep_in=0x81 + id_vcp,
         ep_out=0x01 + id_vcp,
         ep_cmd=0x81 + id_vcp_data,
+        emu_port=UDP_PORT + VCP_PORT_OFFSET,
     )
 
 bus = io.USB(
diff --git a/core/tools/hid-bridge/hid-bridge b/core/tools/hid-bridge/hid-bridge
index 08575e6c4..424648fa0 100755
--- a/core/tools/hid-bridge/hid-bridge
+++ b/core/tools/hid-bridge/hid-bridge
@@ -11,10 +11,10 @@ import logger
 parser = argparse.ArgumentParser()
 parser.add_argument(
     "-e",
-    default=21325,
+    default=21326,
     metavar="port",
     type=int,
-    help="UDP port the utility communicates with, 21325 by default.",
+    help="UDP port the utility communicates with, 21326 by default.",
 )
 parser.add_argument(
     "-l",