AZ-305 is harder than AZ-104. That is the honest answer. The question is by how much, and whether the difficulty is the kind that rewards the study you have already done or requires a different approach entirely.
The prerequisite relationship
AZ-305 has a formal prerequisite: you must hold the Microsoft Certified: Azure Administrator Associate certification (earned by passing AZ-104) before you can earn the Azure Solutions Architect Expert credential. You can sit the AZ-305 exam without holding AZ-104, but you cannot claim the Expert certification until you have passed both.
Cost: Both exams cost $165 USD each via Pearson VUE. Earning the Expert certification requires passing AZ-104 + AZ-305, so budget $330 in exam fees at minimum.
Domain comparison
AZ-104 tests operational configuration across five domains:
- Manage Azure Identities and Governance (15-20%)
- Implement and Manage Storage (15-20%)
- Deploy and Manage Azure Compute Resources (20-25%)
- Implement and Manage Virtual Networking (15-20%)
- Monitor and Maintain Azure Resources (10-15%)
AZ-305 tests architectural design across four domains:
- Design Identity, Governance, and Monitoring Solutions (25-30%)
- Design Data Storage Solutions (25-30%)
- Design Business Continuity Solutions (10-15%)
- Design Infrastructure Solutions (25-30%)
The fundamental difference in what each exam tests
AZ-104 asks: "How do you configure this?" You get a task and you need to know the correct CLI command, the portal setting, or the correct policy assignment. Questions have a right answer and a wrong answer.
AZ-305 asks: "Given these constraints, which design is best and why?" Questions present a scenario with business requirements (cost target, compliance obligation, availability SLA) and ask you to select the most appropriate architecture. The challenge is that multiple options are plausible, and you need to identify which trade-offs the question is actually testing.
This is a fundamentally different cognitive skill. Many people who score well on AZ-104 underestimate AZ-305 because they expect the same kind of "do I know the right command" pattern. AZ-305 requires you to reason about trade-offs, not recall configuration details.
Difficulty by the numbers
Community-reported data from r/AzureCertifications suggests first-attempt pass rates of 70-75% for AZ-104 and 60-65% for AZ-305 among candidates who have done structured preparation. The gap widens for candidates who do not complete case study practice before sitting AZ-305.
What you need to know for AZ-305 that AZ-104 does not prepare you for
- Azure Well-Architected Framework. AZ-305 questions reference the five pillars (Reliability, Security, Cost Optimization, Operational Excellence, Performance Efficiency) and expect you to apply them to design choices.
- Data storage design. Cosmos DB consistency levels, Azure SQL vs Synapse Analytics vs Azure Data Lake trade-offs, storage redundancy patterns for compliance requirements.
- Business continuity architecture. RTO/RPO requirements mapped to specific Azure backup and disaster recovery configurations (Azure Site Recovery, backup vaults, geo-redundant storage).
- Hybrid and multi-region design. ExpressRoute vs VPN Gateway trade-offs, Azure Front Door vs Traffic Manager, designing for latency vs cost vs availability.
Study resources for AZ-305
The Microsoft Learn paths for AZ-305 are the starting point. John Savill's Azure Master Class on YouTube provides architecture-level explanations that map well to the AZ-305 question style. Case study practice is non-negotiable: download the official exam case studies from Microsoft Learn and practice structuring your reasoning before you sit the exam.
Study time estimate
Candidates who passed AZ-104 within the last 6 months typically need 40-60 hours of dedicated AZ-305 preparation. Candidates who earned AZ-104 more than a year ago and have not been doing hands-on architecture work should budget 80+ hours and refresh their AZ-104 knowledge before starting.
Architecture decision example
# AZ-305 tests decisions like this one:
# Bicep snippet for a geo-redundant storage account
# (Understanding when to choose this over LRS or ZRS is an AZ-305 topic)
resource storageAccount 'Microsoft.Storage/storageAccounts@2023-01-01' = {
name: 'stproddatawe001'
location: 'westeurope'
kind: 'StorageV2'
sku: {
name: 'Standard_RAGRS' // Read-access geo-redundant. AZ-305 tests WHY you choose RAGRS vs GRS vs ZRS
}
properties: {
minimumTlsVersion: 'TLS1_2'
allowBlobPublicAccess: false
supportsHttpsTrafficOnly: true
}
}
AZ-104 tests whether you can deploy a storage account. AZ-305 tests whether you know when to use Standard_RAGRS vs Standard_ZRS vs Standard_GRS given a specific RPO and compliance requirement. Study the trade-offs, not just the syntax.