diff --git a/java/com/google/domain/registry/model/contact/ContactResource.java b/java/com/google/domain/registry/model/contact/ContactResource.java
index 36337d09d..830af2a0d 100644
--- a/java/com/google/domain/registry/model/contact/ContactResource.java
+++ b/java/com/google/domain/registry/model/contact/ContactResource.java
@@ -16,6 +16,7 @@ package com.google.domain.registry.model.contact;
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.domain.registry.model.EppResourceUtils.projectResourceOntoBuilderAtTime;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 
 import com.google.common.base.Predicates;
 import com.google.common.collect.FluentIterable;
@@ -60,7 +61,7 @@ import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
     "lastTransferTime",
     "authInfo",
     "disclose" })
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 @Entity
 @ExternalMessagingName("contact")
 public class ContactResource extends EppResource implements ForeignKeyedEppResource {
diff --git a/java/com/google/domain/registry/model/domain/DomainApplication.java b/java/com/google/domain/registry/model/domain/DomainApplication.java
index a39704a44..03a58d2a1 100644
--- a/java/com/google/domain/registry/model/domain/DomainApplication.java
+++ b/java/com/google/domain/registry/model/domain/DomainApplication.java
@@ -14,6 +14,7 @@
 
 package com.google.domain.registry.model.domain;
 
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.util.CollectionUtils.nullToEmptyImmutableCopy;
 
 import com.google.common.collect.ImmutableList;
@@ -50,7 +51,7 @@ import javax.xml.bind.annotation.XmlType;
     "lastEppUpdateClientId",
     "lastEppUpdateTime",
     "authInfo"})
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 @EntitySubclass(index = true)
 @ExternalMessagingName("application")
 public class DomainApplication extends DomainBase {
diff --git a/java/com/google/domain/registry/model/domain/DomainResource.java b/java/com/google/domain/registry/model/domain/DomainResource.java
index d325b83f0..e47867821 100644
--- a/java/com/google/domain/registry/model/domain/DomainResource.java
+++ b/java/com/google/domain/registry/model/domain/DomainResource.java
@@ -17,6 +17,7 @@ package com.google.domain.registry.model.domain;
 import static com.google.common.collect.Sets.intersection;
 import static com.google.domain.registry.model.EppResourceUtils.projectResourceOntoBuilderAtTime;
 import static com.google.domain.registry.model.EppResourceUtils.setAutomaticTransferSuccessProperties;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.util.CollectionUtils.difference;
 import static com.google.domain.registry.util.CollectionUtils.nullToEmptyImmutableCopy;
 import static com.google.domain.registry.util.CollectionUtils.union;
@@ -72,7 +73,7 @@ import javax.xml.bind.annotation.XmlType;
     "registrationExpirationTime",
     "lastTransferTime",
     "authInfo"})
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 @EntitySubclass(index = true)
 @ExternalMessagingName("domain")
 public class DomainResource extends DomainBase implements ForeignKeyedEppResource {
diff --git a/java/com/google/domain/registry/model/host/HostResource.java b/java/com/google/domain/registry/model/host/HostResource.java
index 7b59efcd3..f2d4c8539 100644
--- a/java/com/google/domain/registry/model/host/HostResource.java
+++ b/java/com/google/domain/registry/model/host/HostResource.java
@@ -17,6 +17,7 @@ package com.google.domain.registry.model.host;
 import static com.google.common.collect.Sets.difference;
 import static com.google.common.collect.Sets.union;
 import static com.google.domain.registry.model.EppResourceUtils.projectResourceOntoBuilderAtTime;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.util.CollectionUtils.nullToEmptyImmutableCopy;
 import static com.google.domain.registry.util.DateTimeUtils.START_OF_TIME;
 
@@ -65,7 +66,7 @@ import javax.xml.bind.annotation.XmlType;
     "lastEppUpdateClientId",
     "lastEppUpdateTime",
     "lastTransferTime" })
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 @Entity
 @ExternalMessagingName("host")
 public class HostResource extends EppResource implements ForeignKeyedEppResource {
diff --git a/java/com/google/domain/registry/model/index/DomainApplicationIndex.java b/java/com/google/domain/registry/model/index/DomainApplicationIndex.java
index 4ea83c2a9..fecffbc80 100644
--- a/java/com/google/domain/registry/model/index/DomainApplicationIndex.java
+++ b/java/com/google/domain/registry/model/index/DomainApplicationIndex.java
@@ -17,6 +17,7 @@ package com.google.domain.registry.model.index;
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Strings.isNullOrEmpty;
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.util.CollectionUtils.isNullOrEmpty;
 import static com.google.domain.registry.util.DateTimeUtils.latestOf;
 
@@ -43,7 +44,7 @@ import javax.annotation.Nullable;
  * necessary to query them explicitly from Datastore.
  */
 @Entity
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 public class DomainApplicationIndex extends BackupGroupRoot {
 
   @Id
diff --git a/java/com/google/domain/registry/model/index/ForeignKeyIndex.java b/java/com/google/domain/registry/model/index/ForeignKeyIndex.java
index 6ba1fe1f6..2c67e2e3c 100644
--- a/java/com/google/domain/registry/model/index/ForeignKeyIndex.java
+++ b/java/com/google/domain/registry/model/index/ForeignKeyIndex.java
@@ -16,6 +16,7 @@ package com.google.domain.registry.model.index;
 
 import static com.google.common.collect.Maps.filterValues;
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.util.TypeUtils.instantiate;
 
 import com.google.common.base.Predicate;
@@ -46,17 +47,17 @@ import java.util.Map;
 public abstract class ForeignKeyIndex<E extends EppResource> extends BackupGroupRoot {
 
   /** The {@link ForeignKeyIndex} type for {@link ContactResource} entities. */
-  @Cache
+  @Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
   @Entity
   public static class ForeignKeyContactIndex extends ForeignKeyIndex<ContactResource> {}
 
   /** The {@link ForeignKeyIndex} type for {@link DomainResource} entities. */
-  @Cache
+  @Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
   @Entity
   public static class ForeignKeyDomainIndex extends ForeignKeyIndex<DomainResource> {}
 
   /** The {@link ForeignKeyIndex} type for {@link HostResource} entities. */
-  @Cache
+  @Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
   @Entity
   public static class ForeignKeyHostIndex extends ForeignKeyIndex<HostResource> {}
 
diff --git a/java/com/google/domain/registry/model/ofy/Ofy.java b/java/com/google/domain/registry/model/ofy/Ofy.java
index 4253d5af1..34c8b095b 100644
--- a/java/com/google/domain/registry/model/ofy/Ofy.java
+++ b/java/com/google/domain/registry/model/ofy/Ofy.java
@@ -68,6 +68,15 @@ public class Ofy {
 
   private static final FormattingLogger logger = FormattingLogger.getLoggerForCallerClass();
 
+  /**
+   * Recommended memcache expiration time, which is one hour, specified in seconds.
+   * <p>
+   * This value should used as a cache expiration time for any entities annotated with an Objectify
+   * {@code @Cache} annotation, to put an upper bound on unlikely-but-possible divergence between
+   * memcache and datastore when a memcache write fails.
+   */
+  public static final int RECOMMENDED_MEMCACHE_EXPIRATION = 3600;
+
   /** Default clock for transactions that don't provide one. */
   @NonFinalForTesting
   static Clock clock = new SystemClock();
diff --git a/java/com/google/domain/registry/model/registrar/Registrar.java b/java/com/google/domain/registry/model/registrar/Registrar.java
index 5b3b218a7..8809c2191 100644
--- a/java/com/google/domain/registry/model/registrar/Registrar.java
+++ b/java/com/google/domain/registry/model/registrar/Registrar.java
@@ -26,6 +26,7 @@ import static com.google.common.base.Strings.nullToEmpty;
 import static com.google.common.io.BaseEncoding.base64;
 import static com.google.domain.registry.model.common.EntityGroupRoot.getCrossTldKey;
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.model.registry.Registries.assertTldExists;
 import static com.google.domain.registry.util.CollectionUtils.nullToEmptyImmutableCopy;
 import static com.google.domain.registry.util.CollectionUtils.nullToEmptyImmutableSortedCopy;
@@ -77,7 +78,7 @@ import java.util.Set;
 import java.util.regex.Pattern;
 
 /** Information about a registrar. */
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 @Entity
 public class Registrar extends ImmutableObject implements Buildable, Jsonifiable {
 
diff --git a/java/com/google/domain/registry/model/registrar/RegistrarContact.java b/java/com/google/domain/registry/model/registrar/RegistrarContact.java
index 829a8ce9b..e8056a0c9 100644
--- a/java/com/google/domain/registry/model/registrar/RegistrarContact.java
+++ b/java/com/google/domain/registry/model/registrar/RegistrarContact.java
@@ -19,6 +19,7 @@ import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.collect.Iterables.transform;
 import static com.google.common.collect.Sets.difference;
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.util.CollectionUtils.nullToEmptyImmutableSortedCopy;
 import static com.google.domain.registry.util.ObjectifyUtils.OBJECTS_TO_KEYS;
 
@@ -52,7 +53,7 @@ import java.util.Set;
  * *MUST* also modify the persisted Registrar entity with {@link Registrar#contactsRequireSyncing}
  * set to true.
  */
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 @Entity
 public class RegistrarContact extends ImmutableObject implements Jsonifiable {
 
diff --git a/java/com/google/domain/registry/model/registry/Registry.java b/java/com/google/domain/registry/model/registry/Registry.java
index bfcd937d5..a63f39ba7 100644
--- a/java/com/google/domain/registry/model/registry/Registry.java
+++ b/java/com/google/domain/registry/model/registry/Registry.java
@@ -20,6 +20,7 @@ import static com.google.common.base.Predicates.equalTo;
 import static com.google.common.base.Predicates.not;
 import static com.google.domain.registry.model.common.EntityGroupRoot.getCrossTldKey;
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.model.registry.label.PremiumList.getPremiumPrice;
 import static com.google.domain.registry.util.CollectionUtils.nullToEmptyImmutableCopy;
 import static com.google.domain.registry.util.DateTimeUtils.END_OF_TIME;
@@ -68,7 +69,7 @@ import org.joda.time.Duration;
 import java.util.Set;
 
 /** Persisted per-TLD configuration data. */
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 @Entity
 public class Registry extends BackupGroupRoot implements Buildable {
 
diff --git a/java/com/google/domain/registry/model/registry/label/PremiumList.java b/java/com/google/domain/registry/model/registry/label/PremiumList.java
index 312a269aa..6cadb17ed 100644
--- a/java/com/google/domain/registry/model/registry/label/PremiumList.java
+++ b/java/com/google/domain/registry/model/registry/label/PremiumList.java
@@ -22,6 +22,7 @@ import static com.google.common.collect.Iterables.partition;
 import static com.google.domain.registry.model.common.EntityGroupRoot.getCrossTldKey;
 import static com.google.domain.registry.model.ofy.ObjectifyService.allocateId;
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.util.CollectionUtils.nullToEmpty;
 import static com.google.domain.registry.util.CollectionUtils.nullToEmptyImmutableCopy;
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
@@ -68,7 +69,7 @@ import javax.annotation.Nullable;
  * A premium list entity, persisted to Datastore, that is used to check domain label prices.
  */
 @Entity
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 public final class PremiumList extends BaseDomainLabelList<Money, PremiumList.PremiumListEntry> {
 
   /** The number of premium list entry entities that are created and deleted per batch. */
@@ -196,7 +197,7 @@ public final class PremiumList extends BaseDomainLabelList<Money, PremiumList.Pr
    * single label on a given TLD.
    */
   @Entity
-  @Cache
+  @Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
   public static class PremiumListEntry extends DomainLabelEntry<Money, PremiumListEntry>
       implements Buildable {
 
diff --git a/java/com/google/domain/registry/model/registry/label/ReservedList.java b/java/com/google/domain/registry/model/registry/label/ReservedList.java
index af60e4789..50c7bf78d 100644
--- a/java/com/google/domain/registry/model/registry/label/ReservedList.java
+++ b/java/com/google/domain/registry/model/registry/label/ReservedList.java
@@ -19,6 +19,7 @@ import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
 import static com.google.domain.registry.model.common.EntityGroupRoot.getCrossTldKey;
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.model.registry.label.ReservationType.FULLY_BLOCKED;
 import static com.google.domain.registry.model.registry.label.ReservationType.RESERVED_FOR_ANCHOR_TENANT;
 import static com.google.domain.registry.model.registry.label.ReservationType.UNRESERVED;
@@ -55,7 +56,7 @@ import javax.annotation.Nullable;
  * A reserved list entity, persisted to Datastore, that is used to check domain label reservations.
  */
 @Entity
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 public final class ReservedList
     extends BaseDomainLabelList<ReservationType, ReservedList.ReservedListEntry> {
 
diff --git a/java/com/google/domain/registry/model/server/ServerSecret.java b/java/com/google/domain/registry/model/server/ServerSecret.java
index d76a21f96..c8b271bb4 100644
--- a/java/com/google/domain/registry/model/server/ServerSecret.java
+++ b/java/com/google/domain/registry/model/server/ServerSecret.java
@@ -15,6 +15,7 @@
 package com.google.domain.registry.model.server;
 
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 
 import com.google.domain.registry.model.annotations.NotBackedUp;
 import com.google.domain.registry.model.annotations.NotBackedUp.Reason;
@@ -29,7 +30,7 @@ import java.util.UUID;
 
 /** A secret number used for generating tokens (such as XSRF tokens). */
 @Entity
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 @Unindex
 @NotBackedUp(reason = Reason.AUTO_GENERATED)
 public class ServerSecret extends CrossTldSingleton {
diff --git a/java/com/google/domain/registry/model/tmch/ClaimsListShard.java b/java/com/google/domain/registry/model/tmch/ClaimsListShard.java
index 903313646..83db49e55 100644
--- a/java/com/google/domain/registry/model/tmch/ClaimsListShard.java
+++ b/java/com/google/domain/registry/model/tmch/ClaimsListShard.java
@@ -19,6 +19,7 @@ import static com.google.common.base.Preconditions.checkState;
 import static com.google.common.base.Verify.verify;
 import static com.google.domain.registry.model.ofy.ObjectifyService.allocateId;
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 import static com.google.domain.registry.util.CacheUtils.memoizeWithShortExpiration;
 import static com.google.domain.registry.util.DateTimeUtils.START_OF_TIME;
 
@@ -245,7 +246,7 @@ public class ClaimsListShard extends ImmutableObject {
    * that is live.
    */
   @Entity
-  @Cache
+  @Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
   @NotBackedUp(reason = Reason.EXTERNALLY_SOURCED)
   public static class ClaimsListSingleton extends CrossTldSingleton {
     Key<ClaimsListRevision> activeRevision;
diff --git a/java/com/google/domain/registry/model/tmch/TmchCrl.java b/java/com/google/domain/registry/model/tmch/TmchCrl.java
index 054059eb8..4784dcfb0 100644
--- a/java/com/google/domain/registry/model/tmch/TmchCrl.java
+++ b/java/com/google/domain/registry/model/tmch/TmchCrl.java
@@ -16,6 +16,7 @@ package com.google.domain.registry.model.tmch;
 
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.domain.registry.model.ofy.ObjectifyService.ofy;
+import static com.google.domain.registry.model.ofy.Ofy.RECOMMENDED_MEMCACHE_EXPIRATION;
 
 import com.google.domain.registry.model.annotations.NotBackedUp;
 import com.google.domain.registry.model.annotations.NotBackedUp.Reason;
@@ -32,7 +33,7 @@ import javax.annotation.concurrent.Immutable;
 
 /** Datastore singleton for ICANN's TMCH CA certificate revocation list (CRL). */
 @Entity
-@Cache
+@Cache(expirationSeconds = RECOMMENDED_MEMCACHE_EXPIRATION)
 @Immutable
 @NotBackedUp(reason = Reason.EXTERNALLY_SOURCED)
 public final class TmchCrl extends CrossTldSingleton {