U.S. stock markets ended on a positive note in August after mixed June and July. The astonishing bull run of Wall Street, which started in 2023, has continued this year albeit at a slow pace.
At this stage, we have identified five growth stocks that investors should purchase to strengthen their portfolios in September. Growth investors are primarily focused on stocks with aggressive earnings or revenue growth, which should propel prices higher in the future.
The stocks are: Comfort Systems USA Inc. FIX, Quanta Services Inc. PWR, Seagate Technology Holdings plc STX, Sandisk Corp. SNDK and Semtech Corp. SMTC. Each of our picks sports a Zacks Rank #1 (Strong Buy) and has a Growth Score of A. You can see the complete list of today’s Zacks #1 Rank stocks here.
The chart below shows the price performance of our five picks in the past month.
Image Source: Zacks Investment Research
Comfort Systems USA Inc.
Comfort Systems operates primarily in the commercial and industrial heating, ventilation and air conditioning (HVAC) markets. The data center boom, driven by AI, cloud computing, and high-performance computing, is fueling demand for specialized HVAC solutions from FIX.
Cooling systems for these facilities should deliver precise and reliable performance, prompting investments in advanced technologies such as liquid cooling and modular units. This segment is becoming a significant growth driver for FIX, offering high-margin growth and attracting M&A activity.
Backlog as of June 30, 2026, totaled $14.06 billion, increasing 12.9% from $12.45 billion at March 31, 2026, and jumping 73.2% from $8.12 billion reported a year ago. On a same-store basis, backlog climbed to $13.70 billion from $8.12 billion in the year-ago period.
Solid Estimate Revisions
Comfort Systems has an expected revenue and earnings growth rate of 38.3% and 60.7%, for the current year. The Zacks Consensus Estimate for the current year’s earnings has improved 0.04% over the last 30 days.
Quanta Services Inc.
Quanta Services is well-positioned to capitalize on robust infrastructure spending across utility, power generation, technology and load center markets. The ongoing expansion of AI data centers, grid modernization, renewable generation and advanced manufacturing is driving customers to undertake larger, multiyear infrastructure programs.
Surging AI-related power demand and expanding utility investments are driving data center project opportunities, making data centers a central pillar of PWR’s long-term growth strategy. The company is heavily investing in deepening its vertical supply chain to offset the ongoing global uncertainties and rising inflation.
These favorable trends helped drive total backlog to a record $53.4 billion as of June 30, 2026, up 49% year over year from $35.8 billion in June 2025. The increase was broad-based, with Electric Infrastructure Solutions backlog rising year over year to $43.8 billion from $30.3 billion, while Underground and Infrastructure Solutions backlog climbed to $9.7 billion from $5.6 billion.
Solid Estimate Revisions
Quanta has an expected revenue and earnings growth rate of 38.4% and 52.3%, respectively, for the current year. The Zacks Consensus Estimate for the current year’s earnings has improved 15.5% over the last 60 days.
Seagate Technology Holdings plc
Seagate is benefiting from a shift in AI workloads from short-lived compute jobs to persistent data reuse. Inference, agentic applications, robotics and autonomous systems all create reasons to retain historical, video and sensor data. That supports a tiered storage model in which cost-efficient hard drives remain central.
STX’s AI workloads expand the need for persistent data. AI systems need context. In agentic applications, key-value cache data can be retained and reused across interactions, reducing the need to recompute information already generated. That dynamic is showing up in demand.
Seagate’s Mozaic 4 platform can support drives of up to 44 terabytes and is ramping with the two largest global cloud service providers. Mozaic 5, a five-plus-terabyte-per-disk platform, is scheduled for qualification shipments in late calendar 2027. STX has also pointed to a 50-terabyte drive as the next step after Mozaic 4.
Solid Estimate Revisions
Seagate has an expected revenue and earnings growth rate of 55.2% and more than 100%, for the current year (ending June 2027). The Zacks Consensus Estimate for the current year’s earnings has improved 28.7% over the last 60 days.
Sandisk Corp.
Sandisk — a leading flash and advanced memory technology innovator — is set to maintain its astonishing momentum. SNDK has benefited from the structural shift toward AI computing, which requires significantly more NAND flash storage per deployment compared with traditional workloads.
AI training models and inference applications generate massive data volumes that demand high-performance enterprise solid-state drives, while edge devices need greater storage capacity to support on-device AI features.
This creates a favorable demand environment where SNDK can command premium pricing for its advanced technology products while maintaining disciplined supply allocation. SNDK’s BiCS8 quad-level cell storage product continues to advance through qualification with two major hyperscalers. The extended joint venture agreement with Kioxia Corporation through December 2034 positions Sandisk favorably in the AI memory and storage space.
Solid Estimate Revisions
Sandisk has an expected revenue and earnings growth rate of more than 100%, each for the current year (ending June 2027). The Zacks Consensus Estimate for the current year’s earnings has improved 7.3% over the last 30 days.
Semtech Corp.
Semtech is benefiting from rising AI data center networking demand as 800G remains active and 1.6T FiberEdge and CopperEdge ramps broaden its content opportunity. LoRa is extending across industrial, smart-home and mass-market consumer applications, while premium-device protection and sensing add another growth avenue.
Portfolio optimization and photonics expansion should support a higher-margin mix, and cash generation is funding capacity and product investment. SMTC’s data center business is scaling as 800G demand is complemented by 1.6T FiberEdge and CopperEdge ramps.
In second-quarter fiscal 2027, data center net sales reached a record $100 million, up 39% sequentially and 91% year over year. FiberEdge TIA and driver solutions are designed into every major module provider in the company’s target markets, with some sole-source positions.
SMTC expects 1.6T FiberEdge market share to exceed 50% by fiscal 2027-end, while CopperEdge is already capturing the majority of the linear equalizer market. For third-quarter fiscal 2027, management projects data center sales growth of 45% sequentially and 160% year over year, with momentum expected to continue through fiscal 2028.
Solid Estimate Revisions
Semtech has an expected revenue and earnings growth rate of 41.5% and more than 100%, respectively, for the current year (ending January 2027). The Zacks Consensus Estimate for the current year’s earnings has improved 30.8% in the last 30 days.
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Quanta Services, Inc. (PWR): Free Stock Analysis Report
Seagate Technology Holdings PLC (STX): Free Stock Analysis Report
Sandisk Corporation (SNDK): Free Stock Analysis Report
Semtech Corporation (SMTC): Free Stock Analysis Report
Comfort Systems USA, Inc. (FIX): Free Stock Analysis Report
This article originally published on Zacks Investment Research (zacks.com).