diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
index 83e82bd2880d..7c6db070dfc0 100644
--- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
+++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
@@ -1457,7 +1457,7 @@ int PipelineHandlerRPi::prepareBuffers(Camera *camera)
 	RPiCameraData *data = cameraData(camera);
 	unsigned int minUnicamBuffers = data->config_.minUnicamBuffers;
 	unsigned int minTotalUnicamBuffers = data->config_.minTotalUnicamBuffers;
-	unsigned int numRawBuffers = 0;
+	unsigned int numRawBuffers = 0, minIspBuffers = 1;
 	int ret;
 
 	for (Stream *s : camera->streams()) {
@@ -1481,8 +1481,21 @@ int PipelineHandlerRPi::prepareBuffers(Camera *camera)
 					minTotalUnicamBuffers = 0;
 				}
 			}
-
-			break;
+		} else if (s == &data->isp_[Isp::Output0]) {
+			/*
+			 * Since the ISP runs synchronous with the IPA and requests,
+			 * we only ever need a maximum of one internal buffer. Any
+			 * buffers the application wants to hold onto will already
+			 * be exported through PipelineHandlerRPi::exportFrameBuffers().
+			 *
+			 * However, as above, if the application provides a guarantee
+			 * that the buffer will always be provided for the ISP Output0
+			 * stream in a Request, we don't need any internal buffers
+			 * allocated.
+			 */
+			if (!data->dropFrameCount_ &&
+			    s->configuration().hints & StreamConfiguration::Hint::MandatoryStream)
+				minIspBuffers = 0;
 		}
 	}
 
@@ -1518,12 +1531,14 @@ int PipelineHandlerRPi::prepareBuffers(Camera *camera)
 			 * so allocate the minimum required to avoid frame drops.
 			 */
 			numBuffers = data->config_.minTotalUnicamBuffers;
+		} else if (stream == &data->isp_[Isp::Output0]) {
+			/* Buffer count for this is handled in the earlier loop above. */
+			numBuffers = minIspBuffers;
 		} else {
 			/*
-			 * Since the ISP runs synchronous with the IPA and requests,
-			 * we only ever need one set of internal buffers. Any buffers
-			 * the application wants to hold onto will already be exported
-			 * through PipelineHandlerRPi::exportFrameBuffers().
+			 * Same reasoning as for ISP Output 0, we only ever need
+			 * a maximum of one internal buffer for Output1 (required
+			 * for colour denoise) and ISP statistics.
 			 */
 			numBuffers = 1;
 		}