diff --git a/modules/dasBidAdapter.js b/modules/dasBidAdapter.js
index 76e70f38f9a..5203e126a1f 100644
--- a/modules/dasBidAdapter.js
+++ b/modules/dasBidAdapter.js
@@ -105,7 +105,7 @@ function buildUserIds(customParams) {
 
 function getNpaFromPubConsent(pubConsent) {
   const params = new URLSearchParams(pubConsent);
-  return params.get('npa') == '1';
+  return params.get('npa') === '1';
 }
 
 function buildOpenRTBRequest(bidRequests, bidderRequest) {
@@ -113,7 +113,7 @@ function buildOpenRTBRequest(bidRequests, bidderRequest) {
     bidRequests[0].params,
     bidderRequest,
   );
-  const imp = bidRequests.map((bid, index) => {
+  const imp = bidRequests.map((bid) => {
     const sizes = getAdUnitSizes(bid);
     const imp = {
       id: bid.bidId,
@@ -270,11 +270,29 @@ export const spec = {
 
   buildRequests: function (validBidRequests, bidderRequest) {
     const data = buildOpenRTBRequest(validBidRequests, bidderRequest);
-    const jsonData = encodeURIComponent(JSON.stringify(data));
+    const jsonData = JSON.stringify(data);
+    const baseUrl = getEndpoint(data.ext.network);
+    const fullUrl = `${baseUrl}?data=${encodeURIComponent(jsonData)}`;
+
+    // Switch to POST if URL exceeds 8k characters
+    if (fullUrl.length > 8192) {
+      return {
+        method: 'POST',
+        url: baseUrl,
+        data: jsonData,
+        options: {
+          withCredentials: true,
+          crossOrigin: true,
+          customHeaders: {
+            'Content-Type': 'text/plain'
+          }
+        },
+      };
+    }
 
     return {
       method: 'GET',
-      url: `${getEndpoint(data.ext.network)}?data=${jsonData}`,
+      url: fullUrl,
       options: {
         withCredentials: true,
         crossOrigin: true,
diff --git a/test/spec/modules/dasBidAdapter_spec.js b/test/spec/modules/dasBidAdapter_spec.js
index 714360cc205..07b86210c74 100644
--- a/test/spec/modules/dasBidAdapter_spec.js
+++ b/test/spec/modules/dasBidAdapter_spec.js
@@ -178,217 +178,303 @@ describe('dasBidAdapter', function () {
       expect(payload.imp[0].tagid).to.equal('slot1');
       expect(payload.imp[0].banner.format[0]).to.deep.equal({ w: 300, h: 250 });
     });
-  });
 
-  describe('interpretResponse', function () {
-    const serverResponse = {
-      body: {
-        seatbid: [{
-          bid: [{
-            impid: 'bid123',
-            price: 3.5,
-            w: 300,
-            h: 250,
-            adm: '<creative>',
-            crid: 'crid123',
-            mtype: 1,
-            adomain: ['advertiser.com']
-          }]
-        }],
-        cur: 'USD'
+    it('should use GET method when URL is under 8192 characters', function () {
+      const request = spec.buildRequests(bidRequests, bidderRequest);
+      expect(request.method).to.equal('GET');
+      expect(request.url).to.include('?data=');
+      expect(request.data).to.be.undefined;
+    });
+
+    it('should switch to POST method when URL exceeds 8192 characters', function () {
+      // Create a large bid request that will result in URL > 8k characters
+      const largeBidRequests = [];
+      for (let i = 0; i < 50; i++) {
+        largeBidRequests.push({
+          bidId: `bid${i}`.repeat(20), // Make bid IDs longer
+          params: {
+            site: `site${i}`.repeat(50),
+            area: `area${i}`.repeat(50),
+            slot: `slot${i}`.repeat(50),
+            network: 'network1',
+            pageContext: {
+              du: `https://very-long-url-example-${i}.com`.repeat(10),
+              dr: `https://very-long-referrer-url-${i}.com`.repeat(10),
+              dv: `version-${i}`.repeat(20),
+              keyWords: Array(20).fill(`keyword${i}`),
+              capping: `cap${i}`.repeat(20),
+              keyValues: {
+                [`key${i}`]: `value${i}`.repeat(50)
+              }
+            },
+            customParams: {
+              [`param${i}`]: `value${i}`.repeat(50)
+            }
+          },
+          mediaTypes: {
+            banner: {
+              sizes: [[300, 250], [728, 90], [970, 250]]
+            }
+          }
+        });
       }
-    };
 
-    it('should return proper bid response', function () {
-      const bidResponses = spec.interpretResponse(serverResponse);
-
-      expect(bidResponses).to.be.an('array').with.lengthOf(1);
-      expect(bidResponses[0]).to.deep.include({
-        requestId: 'bid123',
-        cpm: 3.5,
-        currency: 'USD',
-        width: 300,
-        height: 250,
-        ad: '<creative>',
-        creativeId: 'crid123',
-        netRevenue: true,
-        ttl: 300,
-        mediaType: 'banner'
-      });
-      expect(bidResponses[0].meta.advertiserDomains).to.deep.equal(['advertiser.com']);
+      const request = spec.buildRequests(largeBidRequests, bidderRequest);
+
+      expect(request.method).to.equal('POST');
+      expect(request.url).to.equal('https://csr.onet.pl/network1/bid');
+      expect(request.data).to.be.a('string');
+
+      // Check if data is valid JSON (not URL-encoded form data)
+      const payload = JSON.parse(request.data);
+      expect(payload.id).to.equal('reqId123');
+      expect(payload.imp).to.be.an('array');
+      expect(request.options.customHeaders['Content-Type']).to.equal('text/plain');
     });
 
-    it('should return empty array when no valid responses', function () {
-      expect(spec.interpretResponse({ body: null })).to.be.an('array').that.is.empty;
-      expect(spec.interpretResponse({ body: {} })).to.be.an('array').that.is.empty;
-      expect(spec.interpretResponse({ body: { seatbid: [] } })).to.be.an('array').that.is.empty;
+    it('should create valid POST data format', function () {
+      // Create a request that will trigger POST
+      const largeBidRequests = Array(50).fill(0).map((_, i) => ({
+        bidId: `bid${i}`.repeat(20),
+        params: {
+          site: `site${i}`.repeat(50),
+          area: `area${i}`.repeat(50),
+          slot: `slot${i}`.repeat(50),
+          network: 'network1',
+          pageContext: {
+            du: `https://very-long-url-example-${i}.com`.repeat(10),
+            dr: `https://very-long-referrer-url-${i}.com`.repeat(10),
+            keyWords: Array(10).fill(`keyword${i}`)
+          }
+        },
+        mediaTypes: {
+          banner: {
+            sizes: [[300, 250]]
+          }
+        }
+      }));
+
+      const request = spec.buildRequests(largeBidRequests, bidderRequest);
+
+      expect(request.method).to.equal('POST');
+
+      // Parse the POST data as JSON (not URL-encoded)
+      const payload = JSON.parse(request.data);
+      expect(payload.id).to.equal('reqId123');
+      expect(payload.imp).to.be.an('array').with.length(50);
+      expect(payload.ext.network).to.equal('network1');
     });
 
-    it('should return proper bid response for native', function () {
-      const nativeResponse = {
+    describe('interpretResponse', function () {
+      const serverResponse = {
         body: {
           seatbid: [{
             bid: [{
               impid: 'bid123',
               price: 3.5,
-              w: 1,
-              h: 1,
-              adm: JSON.stringify({
-                fields: {
-                  Body: 'Ruszyła sprzedaż mieszkań przy Metrze Dworzec Wileński',
-                  Calltoaction: 'SPRAWDŹ',
-                  Headline: 'Gotowe mieszkania w świetnej lokalizacji (test)',
-                  Image: 'https://ocdn.eu/example.jpg',
-                  Sponsorlabel: 'tak',
-                  Thirdpartyclicktracker: '',
-                  Thirdpartyimpressiontracker: '',
-                  Thirdpartyimpressiontracker2: '',
-                  borderColor: '#CECECE',
-                  click: 'https://mieszkaniaprzymetrodworzec.pl',
-                  responsive: 'nie'
-                },
-                tplCode: '1746213/Native-In-Feed',
-                meta: {
-                  inIFrame: false,
-                  autoscale: 0,
-                  width: '1',
-                  height: '1',
-                  adid: 'das,1778361,669261',
-                  actioncount: 'https://csr.onet.pl/eclk/...',
-                  slot: 'right2',
-                  adclick: 'https://csr.onet.pl/clk/...',
-                  container_wrapper: '<div id="[CREATIVE_APPEND_THIS]"><div style="...">REKLAMA</div></div>',
-                  prebid_native: true
-                }
-              }),
-              mtype: 4
+              w: 300,
+              h: 250,
+              adm: '<creative>',
+              crid: 'crid123',
+              mtype: 1,
+              adomain: ['advertiser.com']
             }]
           }],
           cur: 'USD'
         }
       };
 
-      const bidResponses = spec.interpretResponse(nativeResponse);
+      it('should return proper bid response', function () {
+        const bidResponses = spec.interpretResponse(serverResponse);
+
+        expect(bidResponses).to.be.an('array').with.lengthOf(1);
+        expect(bidResponses[0]).to.deep.include({
+          requestId: 'bid123',
+          cpm: 3.5,
+          currency: 'USD',
+          width: 300,
+          height: 250,
+          ad: '<creative>',
+          creativeId: 'crid123',
+          netRevenue: true,
+          ttl: 300,
+          mediaType: 'banner'
+        });
+        expect(bidResponses[0].meta.advertiserDomains).to.deep.equal(['advertiser.com']);
+      });
 
-      expect(bidResponses).to.be.an('array').with.lengthOf(1);
-      expect(bidResponses[0]).to.deep.include({
-        requestId: 'bid123',
-        cpm: 3.5,
-        currency: 'USD',
-        width: 1,
-        height: 1,
-        native: {
-          title: 'Gotowe mieszkania w świetnej lokalizacji (test)',
-          body: 'Ruszyła sprzedaż mieszkań przy Metrze Dworzec Wileński',
-          cta: 'SPRAWDŹ',
-          image: {
-            url: 'https://ocdn.eu/example.jpg',
-            width: '1',
-            height: '1'
-          },
-          icon: {
-            url: '',
-            width: '1',
-            height: '1'
-          },
-          clickUrl: 'https://csr.onet.pl/clk/...https://mieszkaniaprzymetrodworzec.pl',
-          body2: '',
-          sponsoredBy: '',
-          clickTrackers: [],
-          impressionTrackers: [],
-          javascriptTrackers: [],
-          sendTargetingKeys: false
-        },
-        netRevenue: true,
-        ttl: 300,
-        mediaType: 'native'
+      it('should return empty array when no valid responses', function () {
+        expect(spec.interpretResponse({ body: null })).to.be.an('array').that.is.empty;
+        expect(spec.interpretResponse({ body: {} })).to.be.an('array').that.is.empty;
+        expect(spec.interpretResponse({ body: { seatbid: [] } })).to.be.an('array').that.is.empty;
       });
 
-      expect(bidResponses[0]).to.not.have.property('ad');
+      it('should return proper bid response for native', function () {
+        const nativeResponse = {
+          body: {
+            seatbid: [{
+              bid: [{
+                impid: 'bid123',
+                price: 3.5,
+                w: 1,
+                h: 1,
+                adm: JSON.stringify({
+                  fields: {
+                    Body: 'Ruszyła sprzedaż mieszkań przy Metrze Dworzec Wileński',
+                    Calltoaction: 'SPRAWDŹ',
+                    Headline: 'Gotowe mieszkania w świetnej lokalizacji (test)',
+                    Image: 'https://ocdn.eu/example.jpg',
+                    Sponsorlabel: 'tak',
+                    Thirdpartyclicktracker: '',
+                    Thirdpartyimpressiontracker: '',
+                    Thirdpartyimpressiontracker2: '',
+                    borderColor: '#CECECE',
+                    click: 'https://mieszkaniaprzymetrodworzec.pl',
+                    responsive: 'nie'
+                  },
+                  tplCode: '1746213/Native-In-Feed',
+                  meta: {
+                    inIFrame: false,
+                    autoscale: 0,
+                    width: '1',
+                    height: '1',
+                    adid: 'das,1778361,669261',
+                    actioncount: 'https://csr.onet.pl/eclk/...',
+                    slot: 'right2',
+                    adclick: 'https://csr.onet.pl/clk/...',
+                    container_wrapper: '<div id="[CREATIVE_APPEND_THIS]"><div style="...">REKLAMA</div></div>',
+                    prebid_native: true
+                  }
+                }),
+                mtype: 4
+              }]
+            }],
+            cur: 'USD'
+          }
+        };
+
+        const bidResponses = spec.interpretResponse(nativeResponse);
+
+        expect(bidResponses).to.be.an('array').with.lengthOf(1);
+        expect(bidResponses[0]).to.deep.include({
+          requestId: 'bid123',
+          cpm: 3.5,
+          currency: 'USD',
+          width: 1,
+          height: 1,
+          native: {
+            title: 'Gotowe mieszkania w świetnej lokalizacji (test)',
+            body: 'Ruszyła sprzedaż mieszkań przy Metrze Dworzec Wileński',
+            cta: 'SPRAWDŹ',
+            image: {
+              url: 'https://ocdn.eu/example.jpg',
+              width: '1',
+              height: '1'
+            },
+            icon: {
+              url: '',
+              width: '1',
+              height: '1'
+            },
+            clickUrl: 'https://csr.onet.pl/clk/...https://mieszkaniaprzymetrodworzec.pl',
+            body2: '',
+            sponsoredBy: '',
+            clickTrackers: [],
+            impressionTrackers: [],
+            javascriptTrackers: [],
+            sendTargetingKeys: false
+          },
+          netRevenue: true,
+          ttl: 300,
+          mediaType: 'native'
+        });
+
+        expect(bidResponses[0]).to.not.have.property('ad');
+      });
     });
-  });
 
-  it('should return empty object when adm in a native response is not JSON', function () {
-    const nativeResponse = {
-      body: {
-        seatbid: [{
-          bid: [{
-            impid: 'bad1',
-            price: 2.0,
-            w: 1,
-            h: 1,
-            adm: 'not-a-json-string',
-            mtype: 4
-          }]
-        }],
-        cur: 'USD'
-      }
-    };
+    it('should return empty object when adm in a native response is not JSON', function () {
+      const nativeResponse = {
+        body: {
+          seatbid: [{
+            bid: [{
+              impid: 'bad1',
+              price: 2.0,
+              w: 1,
+              h: 1,
+              adm: 'not-a-json-string',
+              mtype: 4
+            }]
+          }],
+          cur: 'USD'
+        }
+      };
 
-    const bidResponses = spec.interpretResponse(nativeResponse);
-    expect(bidResponses[0].native).to.deep.equal({});
-  });
+      const bidResponses = spec.interpretResponse(nativeResponse);
+      expect(bidResponses[0].native).to.deep.equal({});
+    });
 
-  it('should return empty object when adm in a native response is missing required fields/meta', function () {
-    const nativeResponse = {
-      body: {
-        seatbid: [{
-          bid: [{
-            impid: 'bad2',
-            price: 2.0,
-            w: 1,
-            h: 1,
-            adm: JSON.stringify({ fields: {} }),
-            mtype: 4
-          }]
-        }],
-        cur: 'USD'
-      }
-    };
+    it('should return empty object when adm in a native response is missing required fields/meta', function () {
+      const nativeResponse = {
+        body: {
+          seatbid: [{
+            bid: [{
+              impid: 'bad2',
+              price: 2.0,
+              w: 1,
+              h: 1,
+              adm: JSON.stringify({ fields: {} }),
+              mtype: 4
+            }]
+          }],
+          cur: 'USD'
+        }
+      };
 
-    const bidResponses = spec.interpretResponse(nativeResponse);
-    expect(bidResponses[0].native).to.deep.equal({});
-  });
+      const bidResponses = spec.interpretResponse(nativeResponse);
+      expect(bidResponses[0].native).to.deep.equal({});
+    });
 
-  it('should return empty object when adm in a native response is empty JSON object', function () {
-    const nativeResponse = {
-      body: {
-        seatbid: [{
-          bid: [{
-            impid: 'bad3',
-            price: 2.0,
-            w: 1,
-            h: 1,
-            adm: JSON.stringify({}),
-            mtype: 4
-          }]
-        }],
-        cur: 'USD'
-      }
-    };
+    it('should return empty object when adm in a native response is empty JSON object', function () {
+      const nativeResponse = {
+        body: {
+          seatbid: [{
+            bid: [{
+              impid: 'bad3',
+              price: 2.0,
+              w: 1,
+              h: 1,
+              adm: JSON.stringify({}),
+              mtype: 4
+            }]
+          }],
+          cur: 'USD'
+        }
+      };
 
-    const bidResponses = spec.interpretResponse(nativeResponse);
-    expect(bidResponses[0].native).to.deep.equal({});
-  });
+      const bidResponses = spec.interpretResponse(nativeResponse);
+      expect(bidResponses[0].native).to.deep.equal({});
+    });
 
-  it('should return empty object when adm in a native response is null or missing', function () {
-    const nativeResponse = {
-      body: {
-        seatbid: [{
-          bid: [{
-            impid: 'bad4',
-            price: 2.0,
-            w: 1,
-            h: 1,
-            adm: null,
-            mtype: 4
-          }]
-        }],
-        cur: 'USD'
-      }
-    };
+    it('should return empty object when adm in a native response is null or missing', function () {
+      const nativeResponse = {
+        body: {
+          seatbid: [{
+            bid: [{
+              impid: 'bad4',
+              price: 2.0,
+              w: 1,
+              h: 1,
+              adm: null,
+              mtype: 4
+            }]
+          }],
+          cur: 'USD'
+        }
+      };
 
-    const bidResponses = spec.interpretResponse(nativeResponse);
-    expect(bidResponses[0].native).to.deep.equal({});
+      const bidResponses = spec.interpretResponse(nativeResponse);
+      expect(bidResponses[0].native).to.deep.equal({});
+    });
   });
 });