HDFC Bank vs ICICI Bank: A Side by Side Look at India's Big Two

HDFC Bank is the larger of the two by balance sheet, especially after its 2023 merger with HDFC Ltd, while ICICI Bank has posted the stronger return metrics in recent years, with return on assets in the region of 2 percent. Neither bank is objectively “better”: one is currently a merger-integration and deposit-rebuild story, the other an execution-and-returns story, and this piece deliberately declares no winner.

That framing matters more than any single number. India’s two largest private sector banks are often discussed as if they were interchangeable, but the questions you should ask of each one right now are different. This article lays out the facts from public disclosures, in rounded and clearly approximate terms, and then shows you the framework for comparing any two banks, using these two as the worked example.

Scale: one merger changed the league table

For most of the last two decades, HDFC Bank and ICICI Bank sat at the top of Indian private banking, with HDFC Bank consistently the larger franchise. Then, in July 2023, HDFC Bank completed its merger with its parent, HDFC Ltd, India’s largest housing finance company. Overnight, a very large mortgage book and its funding moved onto the bank’s balance sheet.

The result is that HDFC Bank is now clearly the biggest private sector bank in India by assets, advances, and deposits, and among the largest banks in the world by market value. ICICI Bank remains a giant in absolute terms, with a nationwide franchise across retail, corporate, and rural banking, but it operates at a meaningfully smaller balance sheet than the merged HDFC Bank.

Scale cuts both ways. A larger balance sheet gives HDFC Bank distribution muscle, pricing power, and a bigger base of customers to cross-sell into. It also means the bank has to mobilise deposits at an enormous absolute scale just to fund normal loan growth, which is exactly the challenge the merger created.

The merger’s effect on HDFC Bank: CASA and the deposit rebuild

HDFC Ltd was a housing finance company. It funded its mortgage book largely through bonds and borrowings rather than deposits, because as a non-bank it did not have access to low-cost current and savings accounts. When that book merged into HDFC Bank, the combined entity inherited a funding mix with a much higher share of borrowings than the standalone bank ever carried.

The most visible symptom was the CASA ratio, the share of deposits held in current and savings accounts. Standalone HDFC Bank had long been known for a strong CASA franchise. Post merger, the reported CASA ratio stepped down into the high 30s percent range, simply because the denominator grew and the acquired book brought no CASA with it.

That is why HDFC Bank’s story since 2023 has been dominated by two priorities: mobilising deposits fast enough to replace expensive borrowings, and rebuilding the net interest margin toward its historical levels. Management commentary has consistently framed this as a multi-year glide path rather than a quick fix. When you read an HDFC Bank quarterly result today, the deposit growth number, the CASA trend, and the margin trajectory are the headline items, more so than loan growth.

ICICI Bank’s run: returns and margins

ICICI Bank’s recent story is very different. After a difficult stretch in the mid-2010s marked by corporate asset quality problems, the bank went through a deep clean-up and a management transition. What followed has been one of the more notable turnarounds in Indian banking.

In recent years ICICI Bank has reported return on assets in the region of 2 percent, which is strong territory for a large universal bank anywhere in the world. Its net interest margin has generally sat in the low-to-mid 4s percent range in recent reporting periods. Treat both of these as approximate, rounded descriptions of a trend rather than precise current figures: margins move with rate cycles, and any specific quarter will differ.

The market narrative around ICICI Bank has therefore shifted from “recovery story” to “execution story”. The questions analysts ask are about sustaining these return levels through a falling or rising rate cycle, maintaining underwriting discipline while growing, and keeping cost efficiency intact. There is no integration overhang to work through, which is precisely what distinguishes it from its larger peer right now.

Asset quality: a strength for both

It is worth saying plainly that both banks currently screen well on asset quality by the standards of Indian banking history. Gross non-performing asset ratios at both HDFC Bank and ICICI Bank have been low in recent years, and provisioning coverage at both has been comfortable. This is a genuine change from the 2015-2019 period, when corporate stress dominated the sector’s headlines, and it reflects both cleaner underwriting and a broadly benign credit cycle.

The nuance is in the mix. HDFC Bank’s book is now heavily weighted toward mortgages after the merger, a secured and historically low-loss asset class in India. ICICI Bank runs a diversified retail-plus-corporate book that it has been growing with visible caution in unsecured segments. In both cases, the thing to watch is not the current NPA number, which is backward looking, but incremental slippages and the mix of new lending.

The comparison framework: five metrics that matter

If you want to compare any two banks, not just these two, a small set of metrics does most of the work. Here is the framework, with qualitative readings for the two banks based on recent public disclosures. Note that these are directional descriptions, not precise figures.

Metric	What it tells you	HDFC Bank (recent picture)	ICICI Bank (recent picture)
Return on assets (ROA)	Overall profitability per rupee of balance sheet	Solid, but diluted by the merger; rebuilding	Higher recently; around 2 percent territory
Net interest margin (NIM)	Core lending profitability	Compressed post merger; recovering gradually	Stronger recently; low-to-mid 4s percent range
CASA ratio	Access to low-cost deposits	Stepped down to high 30s percent post merger; rebuilding	Healthy; a long-standing franchise strength
Gross NPA ratio	Stock of bad loans	Low in recent years	Low in recent years
Cost-to-income ratio	Operating efficiency	Reasonable; scale helps, integration costs weigh	Improved markedly through the turnaround

Read the table as a snapshot of two different phases, not a scorecard. Most of HDFC Bank’s softer readings trace back to one event, the merger, and the open question is the pace of normalisation. Most of ICICI Bank’s stronger readings trace back to a completed turnaround, and the open question is durability.

Put together, the comparison resolves into two distinct research questions rather than one ranking.

For HDFC Bank, the questions are about integration mechanics: how quickly can deposits grow relative to loans, how fast does the CASA ratio climb back, how many quarters until the margin approaches pre-merger territory, and does the mortgage-heavy book deliver the cross-sell the merger promised.

For ICICI Bank, the questions are about sustaining excellence: can a bank already earning top-tier returns keep doing so as rate cycles turn, competition for deposits intensifies, and the unsecured retail cycle matures.

Neither set of questions is inherently better to own, and this article is not telling you to own either. Both franchises are large, profitable, well capitalised, and systemically important. Which story you find more interesting to research is a matter of your own process, and any actual investment decision should involve a SEBI-registered adviser. Altys is not a registered Research Analyst or Investment Adviser, and nothing here is a recommendation.

How to run this comparison yourself

Pull the last eight to twelve quarters of results for both banks from their investor presentations and stock exchange filings. Lay out the five metrics above side by side: ROA, NIM, CASA, gross NPA, and cost-to-income. Then do three things. First, look at direction, not just level: a rebuilding metric and a peaked metric can print the same number while meaning opposite things. Second, tie every anomaly to an event: HDFC Bank’s 2023 numbers make no sense without the merger context, so read the management commentary alongside the ratios. Third, write down the one question each bank has to answer over the next two years, and check each new quarter against that question rather than against the other bank. Comparing two banks well is less about crowning a winner and more about knowing exactly what you are watching for in each.