diff --git a/backend/src/db/migrations/20250512133213_add-external-ca-pki.ts b/backend/src/db/migrations/20250512133213_add-external-ca-pki.ts
index d93f0217b..fd1c42f84 100644
--- a/backend/src/db/migrations/20250512133213_add-external-ca-pki.ts
+++ b/backend/src/db/migrations/20250512133213_add-external-ca-pki.ts
@@ -67,6 +67,8 @@ export async function up(knex: Knex): Promise<void> {
       t.uuid("id", { primaryKey: true }).defaultTo(knex.fn.uuid());
       t.string("type").notNullable();
       t.string("name").notNullable();
+      t.string("projectId").notNullable();
+      t.foreign("projectId").references("id").inTable(TableName.Project).onDelete("CASCADE");
       t.uuid("appConnectionId").nullable();
       t.foreign("appConnectionId").references("id").inTable(TableName.AppConnection);
       t.uuid("dnsAppConnectionId").nullable();
@@ -79,6 +81,13 @@ export async function up(knex: Knex): Promise<void> {
       t.binary("credentials");
       t.json("configuration");
       t.string("status").notNullable();
+      t.unique(["projectId", "name"]);
+    });
+  }
+
+  if (await knex.schema.hasTable(TableName.PkiSubscriber)) {
+    await knex.schema.alterTable(TableName.PkiSubscriber, (t) => {
+      t.string("ttl").nullable().alter();
     });
   }
 }
diff --git a/backend/src/db/schemas/certificates.ts b/backend/src/db/schemas/certificates.ts
index 6bedf01ad..5b832bab4 100644
--- a/backend/src/db/schemas/certificates.ts
+++ b/backend/src/db/schemas/certificates.ts
@@ -25,8 +25,8 @@ export const CertificatesSchema = z.object({
   certificateTemplateId: z.string().uuid().nullable().optional(),
   keyUsages: z.string().array().nullable().optional(),
   extendedKeyUsages: z.string().array().nullable().optional(),
-  projectId: z.string(),
-  pkiSubscriberId: z.string().uuid().nullable().optional()
+  pkiSubscriberId: z.string().uuid().nullable().optional(),
+  projectId: z.string()
 });
 
 export type TCertificates = z.infer<typeof CertificatesSchema>;
diff --git a/backend/src/db/schemas/external-certificate-authorities.ts b/backend/src/db/schemas/external-certificate-authorities.ts
index 5613db355..f36c54770 100644
--- a/backend/src/db/schemas/external-certificate-authorities.ts
+++ b/backend/src/db/schemas/external-certificate-authorities.ts
@@ -13,6 +13,7 @@ export const ExternalCertificateAuthoritiesSchema = z.object({
   id: z.string().uuid(),
   type: z.string(),
   name: z.string(),
+  projectId: z.string(),
   appConnectionId: z.string().uuid().nullable().optional(),
   dnsAppConnectionId: z.string().uuid().nullable().optional(),
   certificateAuthorityId: z.string().uuid(),
diff --git a/backend/src/db/schemas/pki-subscribers.ts b/backend/src/db/schemas/pki-subscribers.ts
index 08db19806..920338327 100644
--- a/backend/src/db/schemas/pki-subscribers.ts
+++ b/backend/src/db/schemas/pki-subscribers.ts
@@ -16,7 +16,7 @@ export const PkiSubscribersSchema = z.object({
   name: z.string(),
   commonName: z.string(),
   subjectAlternativeNames: z.string().array(),
-  ttl: z.string(),
+  ttl: z.string().nullable().optional(),
   keyUsages: z.string().array(),
   extendedKeyUsages: z.string().array(),
   status: z.string()
diff --git a/backend/src/ee/services/audit-log/audit-log-types.ts b/backend/src/ee/services/audit-log/audit-log-types.ts
index dcaaf1bdc..17940ac55 100644
--- a/backend/src/ee/services/audit-log/audit-log-types.ts
+++ b/backend/src/ee/services/audit-log/audit-log-types.ts
@@ -1997,7 +1997,7 @@ interface CreatePkiSubscriber {
     caId?: string;
     name: string;
     commonName: string;
-    ttl: string;
+    ttl?: string;
     subjectAlternativeNames: string[];
     keyUsages: CertKeyUsage[];
     extendedKeyUsages: CertExtendedKeyUsage[];
diff --git a/backend/src/server/routes/v1/certificate-authority-routers/certificate-authority-endpoints.ts b/backend/src/server/routes/v1/certificate-authority-routers/certificate-authority-endpoints.ts
index d5907bf12..ddbbaee46 100644
--- a/backend/src/server/routes/v1/certificate-authority-routers/certificate-authority-endpoints.ts
+++ b/backend/src/server/routes/v1/certificate-authority-routers/certificate-authority-endpoints.ts
@@ -6,15 +6,9 @@ import { readLimit, writeLimit } from "@app/server/config/rateLimiter";
 import { verifyAuth } from "@app/server/plugins/auth/verify-auth";
 import { AuthMode } from "@app/services/auth/auth-type";
 import { CaStatus, CaType } from "@app/services/certificate-authority/certificate-authority-enums";
-import {
-  TCertificateAuthority,
-  TCertificateAuthorityInput
-} from "@app/services/certificate-authority/certificate-authority-types";
+import { TCertificateAuthority } from "@app/services/certificate-authority/certificate-authority-types";
 
-export const registerCertificateAuthorityEndpoints = <
-  T extends TCertificateAuthority,
-  I extends TCertificateAuthorityInput
->({
+export const registerCertificateAuthorityEndpoints = <T extends TCertificateAuthority>({
   server,
   caType,
   createSchema,
@@ -27,13 +21,13 @@ export const registerCertificateAuthorityEndpoints = <
     name: string;
     projectId: string;
     status: CaStatus;
-    configuration: I["configuration"];
+    configuration: T["configuration"];
     disableDirectIssuance: boolean;
   }>;
   updateSchema: z.ZodType<{
     name?: string;
     status?: CaStatus;
-    configuration?: I["configuration"];
+    configuration?: T["configuration"];
     disableDirectIssuance?: boolean;
   }>;
   responseSchema: z.ZodTypeAny;
diff --git a/backend/src/server/routes/v1/pki-subscriber-router.ts b/backend/src/server/routes/v1/pki-subscriber-router.ts
index 93505c8b4..8de6b85e1 100644
--- a/backend/src/server/routes/v1/pki-subscriber-router.ts
+++ b/backend/src/server/routes/v1/pki-subscriber-router.ts
@@ -90,7 +90,8 @@ export const registerPkiSubscriberRouter = async (server: FastifyZodProvider) =>
         ttl: z
           .string()
           .trim()
-          .refine((val) => ms(val) > 0, "TTL must be a positive number")
+          .refine((val) => !val || ms(val) > 0, "TTL must be a positive number")
+          .optional()
           .describe(PKI_SUBSCRIBERS.CREATE.ttl),
         subjectAlternativeNames: validateAltNameField
           .array()
@@ -134,7 +135,7 @@ export const registerPkiSubscriberRouter = async (server: FastifyZodProvider) =>
             caId: subscriber.caId ?? undefined,
             name: subscriber.name,
             commonName: subscriber.commonName,
-            ttl: subscriber.ttl,
+            ttl: subscriber.ttl ?? undefined,
             subjectAlternativeNames: subscriber.subjectAlternativeNames,
             keyUsages: subscriber.keyUsages as CertKeyUsage[],
             extendedKeyUsages: subscriber.extendedKeyUsages as CertExtendedKeyUsage[]
@@ -219,7 +220,7 @@ export const registerPkiSubscriberRouter = async (server: FastifyZodProvider) =>
             caId: subscriber.caId ?? undefined,
             name: subscriber.name,
             commonName: subscriber.commonName,
-            ttl: subscriber.ttl,
+            ttl: subscriber.ttl ?? undefined,
             subjectAlternativeNames: subscriber.subjectAlternativeNames,
             keyUsages: subscriber.keyUsages as CertKeyUsage[],
             extendedKeyUsages: subscriber.extendedKeyUsages as CertExtendedKeyUsage[]
diff --git a/backend/src/services/certificate-authority/acme/acme-certificate-authority-fns.ts b/backend/src/services/certificate-authority/acme/acme-certificate-authority-fns.ts
index b30d7c573..0e2361481 100644
--- a/backend/src/services/certificate-authority/acme/acme-certificate-authority-fns.ts
+++ b/backend/src/services/certificate-authority/acme/acme-certificate-authority-fns.ts
@@ -203,32 +203,44 @@ export const AcmeCertificateAuthorityFns = ({
     await appConnectionService.connectAppConnectionById(appConnection.app as AppConnection, dnsAppConnectionId, actor);
 
     const caEntity = await certificateAuthorityDAL.transaction(async (tx) => {
-      const ca = await certificateAuthorityDAL.create(
-        {
-          projectId,
-          disableDirectIssuance
-        },
-        tx
-      );
-
-      await externalCertificateAuthorityDAL.create(
-        {
-          certificateAuthorityId: ca.id,
-          dnsAppConnectionId,
-          type: CaType.ACME,
-          name,
-          configuration: {
-            directoryUrl,
-            accountEmail,
-            dnsProvider: dnsProviderConfig.provider,
-            hostedZoneId: dnsProviderConfig.hostedZoneId
+      try {
+        const ca = await certificateAuthorityDAL.create(
+          {
+            projectId,
+            disableDirectIssuance
           },
-          status
-        },
-        tx
-      );
+          tx
+        );
 
-      return certificateAuthorityDAL.findByIdWithAssociatedCa(ca.id, tx);
+        await externalCertificateAuthorityDAL.create(
+          {
+            certificateAuthorityId: ca.id,
+            dnsAppConnectionId,
+            type: CaType.ACME,
+            name,
+            projectId,
+            configuration: {
+              directoryUrl,
+              accountEmail,
+              dnsProvider: dnsProviderConfig.provider,
+              hostedZoneId: dnsProviderConfig.hostedZoneId
+            },
+            status
+          },
+          tx
+        );
+
+        return await certificateAuthorityDAL.findByIdWithAssociatedCa(ca.id, tx);
+      } catch (error) {
+        // @ts-expect-error We're expecting a database error
+        // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+        if (error?.error?.code === "23505") {
+          throw new BadRequestError({
+            message: "Certificate authority with the same name already exists in your project"
+          });
+        }
+        throw error;
+      }
     });
 
     if (!caEntity.externalCa?.id) {
diff --git a/backend/src/services/pki-subscriber/pki-subscriber-service.ts b/backend/src/services/pki-subscriber/pki-subscriber-service.ts
index a08f0f360..2cb80bd0f 100644
--- a/backend/src/services/pki-subscriber/pki-subscriber-service.ts
+++ b/backend/src/services/pki-subscriber/pki-subscriber-service.ts
@@ -440,7 +440,7 @@ export const pkiSubscriberServiceFactory = ({
 
     const caCertObj = new x509.X509Certificate(decryptedCaCert);
     const notBeforeDate = new Date();
-    const notAfterDate = new Date(new Date().getTime() + ms(subscriber.ttl));
+    const notAfterDate = new Date(new Date().getTime() + ms(subscriber.ttl ?? "0"));
     const caCertNotBeforeDate = new Date(caCertObj.notBefore);
     const caCertNotAfterDate = new Date(caCertObj.notAfter);
 
diff --git a/backend/src/services/pki-subscriber/pki-subscriber-types.ts b/backend/src/services/pki-subscriber/pki-subscriber-types.ts
index 83c45e11f..a26a36a4c 100644
--- a/backend/src/services/pki-subscriber/pki-subscriber-types.ts
+++ b/backend/src/services/pki-subscriber/pki-subscriber-types.ts
@@ -12,7 +12,7 @@ export type TCreatePkiSubscriberDTO = {
   name: string;
   commonName: string;
   status: PkiSubscriberStatus;
-  ttl: string;
+  ttl?: string;
   subjectAlternativeNames: string[];
   keyUsages: CertKeyUsage[];
   extendedKeyUsages: CertExtendedKeyUsage[];
diff --git a/frontend/src/hooks/api/pkiSubscriber/types.ts b/frontend/src/hooks/api/pkiSubscriber/types.ts
index 6b477f9bd..20f7bbcc0 100644
--- a/frontend/src/hooks/api/pkiSubscriber/types.ts
+++ b/frontend/src/hooks/api/pkiSubscriber/types.ts
@@ -24,7 +24,7 @@ export type TCreatePkiSubscriberDTO = {
   caId: string;
   name: string;
   commonName: string;
-  ttl: string;
+  ttl?: string;
   subjectAlternativeNames: string[];
   keyUsages: CertKeyUsage[];
   extendedKeyUsages: CertExtendedKeyUsage[];
diff --git a/frontend/src/pages/cert-manager/PkiSubscribersPage/components/PkiSubscriberModal.tsx b/frontend/src/pages/cert-manager/PkiSubscribersPage/components/PkiSubscriberModal.tsx
index 8171a95c9..c2c193e73 100644
--- a/frontend/src/pages/cert-manager/PkiSubscribersPage/components/PkiSubscriberModal.tsx
+++ b/frontend/src/pages/cert-manager/PkiSubscribersPage/components/PkiSubscriberModal.tsx
@@ -45,7 +45,7 @@ const schema = z
     caId: z.string().min(1, "Issuing CA is required"),
     commonName: z.string().trim().min(1, "Common Name is required"),
     subjectAlternativeNames: z.string(),
-    ttl: z.string().trim(),
+    ttl: z.string().trim().optional(),
     keyUsages: z.object({
       [CertKeyUsage.DIGITAL_SIGNATURE]: z.boolean().optional(),
       [CertKeyUsage.KEY_ENCIPHERMENT]: z.boolean().optional(),
@@ -90,6 +90,7 @@ export const PkiSubscriberModal = ({ popUp, handlePopUpToggle }: Props) => {
     handleSubmit,
     reset,
     setValue,
+    watch,
     formState: { isSubmitting }
   } = useForm<FormData>({
     resolver: zodResolver(schema),
@@ -107,6 +108,9 @@ export const PkiSubscriberModal = ({ popUp, handlePopUpToggle }: Props) => {
     }
   });
 
+  const selectedCaId = watch("caId");
+  const selectedCa = cas?.find((ca) => ca.id === selectedCaId);
+
   useEffect(() => {
     if (pkiSubscriber) {
       reset({
@@ -314,97 +318,101 @@ export const PkiSubscriberModal = ({ popUp, handlePopUpToggle }: Props) => {
               </FormControl>
             )}
           />
-          <Controller
-            control={control}
-            name="ttl"
-            render={({ field, fieldState: { error } }) => (
-              <FormControl
-                label="TTL"
-                isError={Boolean(error)}
-                errorText={error?.message}
-                isRequired
-              >
-                <Input {...field} placeholder="2 days, 1d, 2h, 1y, ..." />
-              </FormControl>
-            )}
-          />
-          <Accordion type="single" collapsible className="w-full">
-            <AccordionItem value="key-usages" className="data-[state=open]:border-none">
-              <AccordionTrigger className="h-fit flex-none pl-1 text-sm">
-                <div className="order-1 ml-3">Key Usage</div>
-              </AccordionTrigger>
-              <AccordionContent>
-                <Controller
-                  control={control}
-                  name="keyUsages"
-                  render={({ field: { onChange, value }, fieldState: { error } }) => {
-                    return (
-                      <FormControl
-                        label="Key Usage"
-                        errorText={error?.message}
-                        isError={Boolean(error)}
-                      >
-                        <div className="mb-7 mt-2 grid grid-cols-2 gap-2">
-                          {KEY_USAGES_OPTIONS.map(({ label, value: optionValue }) => {
-                            return (
-                              <Checkbox
-                                id={optionValue}
-                                key={optionValue}
-                                className="data-[state=checked]:bg-primary"
-                                isChecked={value[optionValue]}
-                                onCheckedChange={(state) => {
-                                  onChange({
-                                    ...value,
-                                    [optionValue]: state
-                                  });
-                                }}
-                              >
-                                {label}
-                              </Checkbox>
-                            );
-                          })}
-                        </div>
-                      </FormControl>
-                    );
-                  }}
-                />
-                <Controller
-                  control={control}
-                  name="extendedKeyUsages"
-                  render={({ field: { onChange, value }, fieldState: { error } }) => {
-                    return (
-                      <FormControl
-                        label="Extended Key Usage"
-                        errorText={error?.message}
-                        isError={Boolean(error)}
-                      >
-                        <div className="mb-7 mt-2 grid grid-cols-2 gap-2">
-                          {EXTENDED_KEY_USAGES_OPTIONS.map(({ label, value: optionValue }) => {
-                            return (
-                              <Checkbox
-                                id={optionValue}
-                                key={optionValue}
-                                className="data-[state=checked]:bg-primary"
-                                isChecked={value[optionValue]}
-                                onCheckedChange={(state) => {
-                                  onChange({
-                                    ...value,
-                                    [optionValue]: state
-                                  });
-                                }}
-                              >
-                                {label}
-                              </Checkbox>
-                            );
-                          })}
-                        </div>
-                      </FormControl>
-                    );
-                  }}
-                />
-              </AccordionContent>
-            </AccordionItem>
-          </Accordion>
+          {selectedCa?.type !== CaType.ACME && (
+            <Controller
+              control={control}
+              name="ttl"
+              render={({ field, fieldState: { error } }) => (
+                <FormControl
+                  label="TTL"
+                  isError={Boolean(error)}
+                  errorText={error?.message}
+                  isRequired
+                >
+                  <Input {...field} placeholder="2 days, 1d, 2h, 1y, ..." />
+                </FormControl>
+              )}
+            />
+          )}
+          {selectedCa?.type !== CaType.ACME && (
+            <Accordion type="single" collapsible className="w-full">
+              <AccordionItem value="key-usages" className="data-[state=open]:border-none">
+                <AccordionTrigger className="h-fit flex-none pl-1 text-sm">
+                  <div className="order-1 ml-3">Key Usage</div>
+                </AccordionTrigger>
+                <AccordionContent>
+                  <Controller
+                    control={control}
+                    name="keyUsages"
+                    render={({ field: { onChange, value }, fieldState: { error } }) => {
+                      return (
+                        <FormControl
+                          label="Key Usage"
+                          errorText={error?.message}
+                          isError={Boolean(error)}
+                        >
+                          <div className="mb-7 mt-2 grid grid-cols-2 gap-2">
+                            {KEY_USAGES_OPTIONS.map(({ label, value: optionValue }) => {
+                              return (
+                                <Checkbox
+                                  id={optionValue}
+                                  key={optionValue}
+                                  className="data-[state=checked]:bg-primary"
+                                  isChecked={value[optionValue]}
+                                  onCheckedChange={(state) => {
+                                    onChange({
+                                      ...value,
+                                      [optionValue]: state
+                                    });
+                                  }}
+                                >
+                                  {label}
+                                </Checkbox>
+                              );
+                            })}
+                          </div>
+                        </FormControl>
+                      );
+                    }}
+                  />
+                  <Controller
+                    control={control}
+                    name="extendedKeyUsages"
+                    render={({ field: { onChange, value }, fieldState: { error } }) => {
+                      return (
+                        <FormControl
+                          label="Extended Key Usage"
+                          errorText={error?.message}
+                          isError={Boolean(error)}
+                        >
+                          <div className="mb-7 mt-2 grid grid-cols-2 gap-2">
+                            {EXTENDED_KEY_USAGES_OPTIONS.map(({ label, value: optionValue }) => {
+                              return (
+                                <Checkbox
+                                  id={optionValue}
+                                  key={optionValue}
+                                  className="data-[state=checked]:bg-primary"
+                                  isChecked={value[optionValue]}
+                                  onCheckedChange={(state) => {
+                                    onChange({
+                                      ...value,
+                                      [optionValue]: state
+                                    });
+                                  }}
+                                >
+                                  {label}
+                                </Checkbox>
+                              );
+                            })}
+                          </div>
+                        </FormControl>
+                      );
+                    }}
+                  />
+                </AccordionContent>
+              </AccordionItem>
+            </Accordion>
+          )}
           <div className="mt-4 flex items-center">
             <Button
               className="mr-4"