Microsoft's coding interview is a four-stage process: a recruiter screen, an online assessment or technical phone screen, an onsite "loop" of four to five interviews, and a final "as appropriate" (AA) round with a senior leader who holds hiring authority. The Microsoft engineering interview runs in four main stages. It starts with a recruiter call. Next comes an online assessment or a technical phone screen. After that is a final set of interviews that candidates call the loop, then the team and offer step. The coding bar is real but predictable: expect one problem per interview hour, heavy on strings, arrays, hashing, and linked lists. This plan tells you exactly what to drill and how to spend four weeks doing it.
If you want the live-feedback version of this, our Microsoft company breakdown maps questions to the concepts they test.
The Microsoft loop, stage by stage
The process is not one-size-fits-all. Microsoft's careers site explicitly says the steps after the first screen vary by role, and your recruiter is your source of truth for format and timing. But the common shape is consistent across engineering candidates.
An initial screening call with a recruiter. A phone screen with a hiring manager. A technical interview (for technical roles only). An onsite loop consisting of 4-6 interviews. The interview process is not centralized and may vary depending on the role you apply for. For the loop itself, the loop itself is usually four to five interviews of about an hour each. Most loops now run virtually. Most teams now default to virtual interviews conducted over Microsoft Teams, with the option to interview onsite if you prefer.
Plan for a wait between stages. Reported timelines vary, from about two weeks to two months. Four to eight weeks is the common report. Scheduling and internal approvals make that wait longer for some people.
The "as appropriate" (AA) round
The AA round is Microsoft's most distinctive feature and the one candidates most often misunderstand. It is a final interview conducted by a senior leader who reviews the whole loop's feedback and makes the call. At some point in the evolution of the interview loop, the "As appropriate" stopped being optional. Everybody got an "As appropriate" interview.
Treat the AA like any other technical or behavioral round. If the AA asks a technical question, solve it normally. If the interviewer challenges a story, clarify the concern and add evidence instead of guessing which previous round you are repairing. Do not read the tea leaves. A warm close, a discussion about Microsoft culture, or questions about start dates may feel positive, but none guarantees an offer. A short interview is not automatically bad, either. Hiring decisions depend on the full loop and organizational needs.
One structural note for senior candidates: the behavioral evaluation is baked into technical rounds rather than isolated. Until L64, there's no dedicated behavioral round - instead, all coding and system design rounds include behavioral evaluation components, and you'll typically be told beforehand what the behavioral focus area will be for each round.
What Microsoft actually asks (the coding pattern)
Across the loops we run, Microsoft skews toward string and array manipulation, linked lists, and clean handling of edge cases and integer overflow. These are not exotic problems. They reward candidates who can write correct, well-tested code fast and explain it clearly. Here is the DevInterview question bank ordered by how often Microsoft asks each one.
| Problem | Level | Core pattern |
|---|---|---|
| Longest Substring Without Repeating Characters | Mid/Senior | Sliding window + hash map |
| Median of Two Sorted Arrays | Staff | Binary search on partitions |
| Longest Palindromic Substring | Mid/Senior | Expand around center / DP |
| Zigzag Conversion | Mid/Senior | Simulation |
| Add Two Numbers | Mid/Senior | Linked list + carry |
| Reverse Integer | Mid/Senior | Math + overflow guard |
| String to Integer (atoi) | Mid/Senior | Parsing + edge cases |
| Hand of Straights | Mid/Senior | Greedy + counting |
Two things stand out. First, the highest-frequency questions are string problems: "Longest Substring Without Repeating Characters" and "Longest Palindromic Substring" both reward the two pointers and sliding-window toolkit more than heavy algorithms. Second, Microsoft loves problems where the trap is correctness, not cleverness. "Reverse Integer" and "String to Integer (atoi)" are easy to sketch and easy to fail, because the real test is whether you handle the signed 32-bit overflow boundary and messy input without being reminded.
The 4-week plan
Four weeks is enough if you practice deliberately and out loud. Budget 1.5 to 2 hours on weekdays and one longer session on the weekend. Do not grind 300 random problems; drill the patterns Microsoft repeats and rehearse explaining them.
Week 1: Strings and hashing
Start where Microsoft's frequency is highest. Solve "Longest Substring Without Repeating Characters" until the sliding-window template is automatic, then "Longest Palindromic Substring" with both the expand-around-center and DP approaches so you can discuss the tradeoff. Add "Zigzag Conversion" as a pure simulation warm-up. Reinforce the fundamentals with our String and Hash Table concept sets.
Deliverable by Friday: you can state the time and space complexity of every solution before you run it.
Week 2: Linked lists, math, and parsing
Do "Add Two Numbers" and its follow-ups (what if the digits are stored in forward order?). Then tackle the deceptively simple pair, "Reverse Integer" and "String to Integer (atoi)". Write the overflow check yourself and test the boundaries: INT_MAX, INT_MIN, leading whitespace, a lone + or -, and embedded letters. These are exactly the cases interviewers add as follow-ups. Our guide on handling follow-up questions is worth a read here.
Week 3: Greedy, sorting, and binary search
Solve "Hand of Straights" as a greedy-plus-counting problem, then push into the hardest item on the list: "Median of Two Sorted Arrays". The brute-force merge is O(m+n); the interviewer wants the O(log(min(m,n))) binary-search-on-partitions solution. It is the single most likely question to separate a strong signal from an average one at staff level. Drill the technique with our Binary Search set.
Week 4: Full mock loops
Stop learning new problems. Run timed, end-to-end mocks that mirror the loop: 45 to 60 minutes, one problem, talk the whole time. The most common failure we see is not a missing algorithm; it is candidates who solve silently, then cannot narrate their approach when the AA interviewer probes. Practice against the real bank on our Microsoft practice page and get feedback on communication, not just correctness.
How Microsoft scores you
Coding correctness is table stakes. What differentiates candidates at Microsoft is communication under scrutiny and cultural signal, specifically the "growth mindset" the company screens for. The AA interviewer probes concerns flagged earlier in the loop and weighs how you respond to pushback.
Three habits move your score:
- Clarify before you code. Restate the problem, confirm constraints, and name edge cases (empty input, overflow, duplicates) out loud. On "Reverse Integer" this is the entire point.
- Narrate tradeoffs. For "Longest Palindromic Substring," say why you would pick expand-around-center over DP. Interviewers grade judgment, not memorization.
- Test your own code. Walk a small example through your solution before claiming it works. Silent submission reads as luck.
FAQ
How many coding problems will I face at Microsoft?
Expect roughly one substantial problem per technical hour. The loop itself is usually four to five interviews of about an hour each, and technical rounds typically center on a single coding problem plus follow-ups rather than several rapid-fire questions.
What is the "as appropriate" round and how do I prepare?
It is a final interview by a senior leader with hiring authority who reviews all prior feedback. At some point in the evolution of the interview loop, the "As appropriate" stopped being optional. Everybody got an "As appropriate" interview. Prepare for it exactly like your other rounds: solve any coding question normally and back up your behavioral stories with evidence.
How long does the Microsoft interview process take?
Most candidates report four to eight weeks. Reported timelines vary, from about two weeks to two months. Four to eight weeks is the common report. The longest gap is usually between the phone screen and the loop, because scheduling multiple interviewers takes time.
Are Microsoft interviews virtual or onsite in 2026?
Mostly virtual, with an onsite option. Most teams now default to virtual interviews conducted over Microsoft Teams, with the option to interview onsite if you prefer. Your recruiter confirms the format for your specific loop.
Do senior candidates get a separate behavioral round?
Not until higher levels. Until L64, there's no dedicated behavioral round - instead, all coding and system design rounds include behavioral evaluation components. You will usually be told the behavioral focus for each round in advance.
Sources
- Microsoft Interview Guide: Process, Questions, and How to Prepare (DesignGurus)
- Get a Job at Microsoft: Interview Process and Top Questions (Aced / Exponent)
- Microsoft L63-64 Interview Guides & Questions (Hello Interview)
- Microspeak: The As-Appropriate (AA) interviewer (The Old New Thing, Microsoft)
- Microsoft As-Appropriate Interview Guide (PracHub)