diff --git a/esphome/components/modem/modem_component.cpp b/esphome/components/modem/modem_component.cpp
index ecd2018c66..0c034f0c80 100644
--- a/esphome/components/modem/modem_component.cpp
+++ b/esphome/components/modem/modem_component.cpp
@@ -364,6 +364,7 @@ void ModemComponent::loop() {
             ESP_LOGE(TAG, "modem not ready after hang up");
           }
           this->set_timeout("wait_lost_ip", 60000, [this]() {
+            // often reached on 7600, but not reached on 7670
             ESP_LOGW(TAG, "No lost ip event received. Forcing disconnect state");
 
             this->state_ = ModemComponentState::DISCONNECTED;
@@ -466,11 +467,12 @@ void ModemComponent::poweron_() {
     this->power_transition_ = true;
     this->power_pin_->digital_write(false);
     // min 100 for SIM7600, but min 1200 for SIM800.  min BG96: 650
-    delay(1300);  // NOLINT
+    delay(this->modem_model_ton_[this->model_]);  // NOLINT
     this->power_pin_->digital_write(true);
-    // status will be on from 3s (SIM800) to 12s (SIM7600)
-    ESP_LOGD(TAG, "Will check that the modem is on in 12s...");
-    this->set_timeout("wait_poweron", 12000, [this]() {
+    // use a timout for long wait delay
+    uint32_t tonuart = this->modem_model_tonuart_[this->model_];
+    ESP_LOGD(TAG, "Will check that the modem is on in %.1fs...", float(tonuart) / 1000);
+    this->set_timeout("wait_poweron", tonuart, [this]() {
       Watchdog wdt(60);
       while (!this->get_power_status()) {
         delay(this->command_delay_);
@@ -496,12 +498,12 @@ void ModemComponent::poweroff_() {
       this->power_pin_->digital_write(true);
       delay(10);
       this->power_pin_->digital_write(false);
-      delay(2700);  // NOLINT
+      delay(this->modem_model_toff_[this->model_]);
       this->power_pin_->digital_write(true);
 
-      // will have to wait at least 25s
-      ESP_LOGD(TAG, "Will check that the modem is off in 25s...");
-      this->set_timeout("wait_poweron", 25000, [this]() {
+      uint32_t toffuart = this->modem_model_toffuart_[this->model_];
+      ESP_LOGD(TAG, "Will check that the modem is off in %.1fs...", float(toffuart) / 1000);
+      this->set_timeout("wait_poweron", toffuart, [this]() {
         Watchdog wdt(60);
 
         while (this->get_power_status()) {
diff --git a/esphome/components/modem/modem_component.h b/esphome/components/modem/modem_component.h
index 83a48cec45..5c55c528f0 100644
--- a/esphome/components/modem/modem_component.h
+++ b/esphome/components/modem/modem_component.h
@@ -117,6 +117,31 @@ class ModemComponent : public Component {
   uint32_t command_delay_ = 500;
   // Will be true when power transitionning
   bool power_transition_ = false;
+  // time needed for power_pin to be low for poweron
+  std::unordered_map<ModemModel, uint32_t> modem_model_ton_ = {{ModemModel::BG96, 600},
+                                                               {ModemModel::SIM800, 1300},
+                                                               {ModemModel::SIM7000, 1100},
+                                                               {ModemModel::SIM7070, 1100},
+                                                               {ModemModel::SIM7600, 500}};
+  // time to wait after poweron for uart to be ready
+  std::unordered_map<ModemModel, uint32_t> modem_model_tonuart_ = {{ModemModel::BG96, 4900},
+                                                                   {ModemModel::SIM800, 3000},
+                                                                   {ModemModel::SIM7000, 4500},
+                                                                   {ModemModel::SIM7070, 2500},
+                                                                   {ModemModel::SIM7600, 12000}};
+  // time needed for power_pin to be high for poweroff
+  std::unordered_map<ModemModel, uint32_t> modem_model_toff_ = {{ModemModel::BG96, 650},
+                                                                {ModemModel::SIM800, 200},
+                                                                {ModemModel::SIM7000, 1300},
+                                                                {ModemModel::SIM7070, 1300},
+                                                                {ModemModel::SIM7600, 2800}};
+  // time to wait after for poweroff for uart to be really closed
+  std::unordered_map<ModemModel, uint32_t> modem_model_toffuart_ = {{ModemModel::BG96, 2000},
+                                                                    {ModemModel::SIM800, 3000},
+                                                                    {ModemModel::SIM7000, 1800},
+                                                                    {ModemModel::SIM7070, 1800},
+                                                                    {ModemModel::SIM7600, 25000}};
+
   // separate handler for `on_not_responding` (we want to know when it's ended)
   Trigger<> *not_responding_cb_{nullptr};
   CallbackManager<void(ModemComponentState)> on_state_callback_;